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- Creator:
- Moniri, Saman, Xiao, Xianghui, and Shahani, Ashwin J.
- Description:
- The data file is comprised of 22,500 X-ray projections (15 scans of 1500 projections each) recorded during solidification of Al-Ge-Na. The raw data file is in .hdf format and can be reconstructed into .tiff, e.g., by using the TomoPy toolbox in Python.
- Keyword:
- X-ray microtomography, synchrotron, in situ, 4D materials science, irregular eutectic, growth, and solidification
- Citation to related publication:
- Moniri, S., Xiao, X., & Shahani, A. J. (2019). The mechanism of eutectic modification by trace impurities. Scientific Reports, 9(1), 3381. https://doi.org/10.1038/s41598-019-40455-3
- Discipline:
- Engineering
-
- Creator:
- Hepner, Shadrach, T
- Description:
- This data provided evidence of the presence of a lower hybrid drift instability in a magnetic nozzle. It was used in DOI: 10.1063/5.0012668 to estimate the effective electron collision frequency that it induced in the context of cross-field electron transport. It is also used to determine the effective reduction in heat flux resulting from propagation along magnetic field lines in an upcoming work.
- Keyword:
- Magnetic nozzle, heat flux, plasma instabilities
- Citation to related publication:
- Hepner, S., Jorns, B. (2020). Wave-driven non-classical electron transport in a low temperature magnetically expanding plasma. Appl. Phys. Lett, 116(263502). https://doi.org/10.1063/5.0012668
- Discipline:
- Engineering
-
- Creator:
- Revzen, Shai
- Description:
- This repository contains both the data and python3 code that reads this data and reproduces the relevant figures. The code depends on NumPy >1.17 and matplotlib >3.1 and was tested on python 3.8
- Keyword:
- locomotion, slipping, low Reynolds number, walking, and slithering
- Discipline:
- Science and Engineering
-
- Creator:
- Sun, Hu, Ren, Jiaen, Chen, Yang, Zou, Shasha, Chang, Yurui, Wang, Zihan, and Coster, Anthea
- Description:
- Our research focuses on providing a fully-imputed map of the worldwide total electron content with high resolution and spatial-temporal smoothness. We fill in the missing values of the original Madrigal TEC maps via estimating the latent feature of each latitude and local time along the 2-D grid and give initial guess of the missing regions based on pre-computed spherical harmonics map. The resulting TEC map has high imputation accuracy and the ease of reproducing. All data are in HDF5 format and are easy to read using the h5py package in Python. The TEC map is grouped in folders based on years and each file contains a single-day data of 5-min cadence. Each individual TEC map is of size 181*361. and WARNING: 2023-12-01 the data file for 2019-Jan-03 has badly fitted values. Please avoid using it. All other days' files are ready to use.
- Keyword:
- Total Electron Content, Matrix Completion, VISTA, Spherical Harmonics, and Spatial-Temporal Smoothing
- Citation to related publication:
- Sun, H., Hua, Z., Ren, J., Zou, S., Sun, Y., & Chen, Y. (2022). Matrix completion methods for the total electron content video reconstruction. The Annals of Applied Statistics, 16(3), 1333-1358., Sun, H., Chen, Y., Zou, S., Ren, J., Chang, Y., Wang, Z., & Coster, A. (2023). Complete Global Total Electron Content Map Dataset based on a Video Imputation Algorithm VISTA. Scientific Data, in press., and Zou, S., Ren, J., Wang, Z., Sun, H., & Chen, Y. (2021). Impact of storm-enhanced density (SED) on ion upflow fluxes during geomagnetic storm. Frontiers in Astronomy and Space Sciences, 8, 746429.
- Discipline:
- Science and Engineering
-
- Creator:
- Billings, Gideon H and Johnson-Roberson, Matthew
- Description:
- UWslam is a dataset for underwater stereo and hybrid monocular fisheye + stereo SLAM in natural seafloor environments. The dataset includes a spiral survey of a shallow reef captured with a diver operated stereo rig and 4 hybrid image sequences captured with a deep ocean ROV in different deep ocean environments. Ground truth pose estimates for the spiral stereo trajectory were obtained by processing the image sequence through COLMAP. Ground truth pose estimates for the hybrid sequences were obtained by distributing fiducials on the seafloor before capturing an image sequence and processing the image sequences with the ROS based TagSLAM package.
- Keyword:
- SLAM, Simultaneous Localization and Mapping, Visual Reconstruction, and Underwater
- Citation to related publication:
- G. Billings, R. Camilli and M. Johnson-Roberson, "Hybrid Visual SLAM for Underwater Vehicle Manipulator Systems," in IEEE Robotics and Automation Letters, vol. 7, no. 3, pp. 6798-6805, July 2022, doi: 10.1109/LRA.2022.3176448.
- Discipline:
- Engineering
-
- Creator:
- Billings, Gideon H and Johnson-Roberson, Matthew
- Description:
- UWHandles is a dataset for 6D object pose estimation in underwater fisheye images. It provides 6D pose and 2D bounding box annotations for 3 different graspable handle objects used for ROV manipulation. The dataset consists of 28 image sequences collected in natural seafloor environments with a total of 20,427 annotated frames. and Meta repository for the dataset https://github.com/gidobot/UWHandles
- Keyword:
- Deep Learning, Pose Estimation, and Underwater Vision
- Citation to related publication:
- Billings, G., & Johnson-Roberson, M. (2020). SilhoNet-fisheye: Adaptation of a ROI based object pose estimation network to monocular fisheye images. IEEE Robotics and Automation Letters, 5(3), 4241-4248.
- Discipline:
- Engineering
-
- Creator:
- Mohtat, Peyman, Siegel, Jason B., and Stefanopoulou, Anna G.
- Description:
- The goal here is to study the voltage and expansion response of lithium-ion batteries at different charging rates. Specifically, the goal is to capture the observation of the smoothing of the peaks in dV/dQ and retention of the peaks in d^2 (backslash)delta/dQ^2 at higher C-rates. The retention of the peaks at higher charging rates enables better estimation of the cell capacity. To achieve this goal a reduced order electrochemical and mechanical model with multiple particles with a size distribution is developed. This allows us to capture the smoothing and preservation of the phase transitions in the voltage and expansion measurements at high C-rates, respectively. The model is written in Matlab software.
- Keyword:
- Lithium-ion batteries, Modeling, Multiparticle, Mechanical response, and Electrochemical
- Citation to related publication:
- Mohtat, P., Lee, S., Sulzer, V., Siegel, J. B., & Stefanopoulou, A. G. (2020). Differential Expansion and Voltage Model for Li-ion Batteries at Practical Charging Rates. Journal of The Electrochemical Society, 167(11), 110561. https://doi.org/10.1149/1945-7111/aba5d1
- Discipline:
- Engineering
-
- Creator:
- Mohtat, Peyman, Siegel, Jason B., Stefanopoulou, Anna G., and Lee, Suhak
- Description:
- The focus of this research effort is to systematically study the capability of aging diagnostics using cell expansion under variety of aging conditions and states. The data collection campaign is very important to cover various degradation modes to extract the degradation features that will be used to inform, parameterize, and validate the models developed earlier. In the data collection campaign, we are documenting the evolution of the electrical and mechanical characteristics and especially the reversible mechanical measurement. It is important to note that we collect data using newly developed fixtures that enables the simultaneous measurement of mechanical and electrical response under pseudo-constant pressure.
- Keyword:
- Lithium-ion batteries, Mechanical response, Aging, NMC, and Pouch cells
- Citation to related publication:
- Peyman Mohtat et al. (2021). Reversible and Irreversible Expansion of Lithium-ion Batteries Under a Wide Range of Stress Factors. J. Electrochem. Soc. 168 100520 https://doi.org/10.1149/1945-7111/ac2d3e
- Discipline:
- Engineering
-
- Creator:
- Towne, Aaron S. and Brès, Guillaume
- Description:
- This dataset contains data from a large eddy simulation of a turbulent jet at Mach number 0.9. The dataset contains 10000 time-resolved snapshots of three-dimensional velocity, density, and pressure fields spanning 2000 acoustic time units and also includes pre-processed azimuthal Fourier modes for each snapshot and the mean flow. All data are stored within hdf5 files, and a Matlab script showing how the data can be read and manipulated is provided. Please see the ‘jet_README.pdf’ file for more information. We recommend using the ‘jet_example.zip’ file as an entry point to the dataset. and The dataset is part of “A database for reduced-complexity modeling of fluid flows” (see references below) and is intended to aid in the conception, training, demonstration, evaluation, and comparison of reduced-complexity models for fluid mechanics. The paper introduces the flow setup and computational methods, describes the available data, and provides two examples of how these data can be used for reduced-complexity modeling. Users of these data should cite the two papers listed below.
- Keyword:
- fluid mechanics, jets, and turbulence
- Citation to related publication:
- Towne, A., Dawson, S., Brès, G. A., Lozano-Durán, A., Saxton-Fox, T., Parthasarthy, A., Biler, H., Jones, A. R., Yeh, C.-A., Patel, H., Taira, K. (2022). A database for reduced-complexity modeling of fluid flows. AIAA Journal 61(7): 2867-2892. and Brès, G. A., Jordan, P., Jaunet, V., Le Rallic, M., Cavalieri, A. V. G., Towne, A., Lele, S. K., Colonius, T., Schmidt, O. T. (2018) Importance of the nozzle-exit boundary-layer state in subsonic turbulent jets. J. Fluid Mech., 851:83–124.
- Discipline:
- Engineering and Science
-
- Creator:
- Towne, Aaron, Saxton-Fox, Theresa, and Parthasarthy, Aadhy
- Description:
- This dataset contains experimental measurements of a zero-pressure-gradient flat-plate boundary layer at five different Reynolds numbers collected using particle image velocimetry. For each Reynolds number, the dataset contains approximately 6000 snapshots of planar velocity fields as well as raw particle image pairs. All data are stored within hdf5 files, and a Matlab script showing how the data can be read and manipulated is provided. Please see the ‘BLexp_README.pdf’ file for more information. We recommend using the ‘BLexp_example.zip’ file as an entry point to the dataset. and The dataset is part of “A database for reduced-complexity modeling of fluid flows” (see references below) and is intended to aid in the conception, training, demonstration, evaluation, and comparison of reduced-complexity models for fluid mechanics. The paper introduces the flow setup and computational methods, describes the available data, and provides an example of how these data can be used for reduced-complexity modeling. Users of these data should cite the papers listed below.
- Keyword:
- fluid mechanics
- Citation to related publication:
- Towne, A., Dawson, S., Brès, G. A., Lozano-Durán, A., Saxton-Fox, T., Parthasarthy, A., Biler, H., Jones, A. R., Yeh, C.-A., Patel, H., Taira, K. (2022). A database for reduced-complexity modeling of fluid flows. AIAA Journal 61(7): 2867-2892.
- Discipline:
- Engineering and Science
-
- Creator:
- Towne, Aaron S. and Lozano-Durán, Adrián
- Description:
- This dataset contains data from two direct numerical simulations of a turbulent zero-pressure-gradient flat-plate boundary layer spanning friction Reynolds numbers from 292 to 728 (BL1) and 488 to 1024 (BL2). The dataset contains time-resolved snapshots of the three-dimensional velocity field for both cases: roughly 10,000 snapshots spanning 20 eddy-turnover times for BL1 and 7,500 snapshots spanning 7 eddy-turnover times for BL2 . Also included for both cases are pre-processed correlations at several wall-normal distances, mean and root-mean-squared velocity and vorticity profiles, several boundary-layer metrics, and time-resolved velocity data in the streamwise-wall-normal plane. All data are stored within hdf5 files, and a Matlab script showing how the data can be read and manipulated is provided. Please see the ‘BLdns_README.pdf’ file for more information. We recommend using the ‘BLdns_example.zip’ file as an entry point to the dataset. and The dataset is part of “A database for reduced-complexity modeling of fluid flows” (see references below) and is intended to aid in the conception, training, demonstration, evaluation, and comparison of reduced-complexity models for fluid mechanics. The paper introduces the flow setup and computational methods, describes the available data, and provides an example of how these data can be used for reduced-complexity modeling. Users of these data should cite the paper listed below.
- Keyword:
- fluid mechanics, boundary layer, and turbulence
- Citation to related publication:
- Towne, A., Dawson, S., Brès, G. A., Lozano-Durán, A., Saxton-Fox, T., Parthasarthy, A., Biler, H., Jones, A. R., Yeh, C.-A., Patel, H., Taira, K. (2022). A database for reduced-complexity modeling of fluid flows. AIAA Journal 61(7): 2867-2892.
- Discipline:
- Engineering and Science
-
- Creator:
- Towne, Aaron, Yeh, Chi-An., Patel, Het, and Taira, Kunihiko
- Description:
- This dataset contains data from a three-dimensional large eddy simulation of Mach 0.3 flow over a NACA 0012 airfoil at Reynolds number 23,000, which features a transitional boundary layer, separation over a recirculation bubble, and a turbulent wake. The dataset contains 16,000 time-resolved snapshots of the mid-span and spanwise-averaged velocity fields. All data are stored within hdf5 files, and a Matlab script showing how the data can be read and manipulated is provided. Please see the ‘airfoilLES_README.pdf’ file for more information. We recommend using the ‘airfoilLES_example.zip’ file as an entry point to the dataset. and The dataset is part of “A database for reduced-complexity modeling of fluid flows” (see references below) and is intended to aid in the conception, training, demonstration, evaluation, and comparison of reduced-complexity models for fluid mechanics. The paper introduces the flow setup and computational methods, describes the available data, and provides an example of how these data can be used for reduced-complexity modeling. Users of these data should cite the papers listed below.
- Citation to related publication:
- Towne, A., Dawson, S., Brès, G. A., Lozano-Durán, A., Saxton-Fox, T., Parthasarthy, A., Biler, H., Jones, A. R., Yeh, C.-A., Patel, H., Taira, K. (2022). A database for reduced-complexity modeling of fluid flows. AIAA Journal 61(7): 2867-2892. and Yeh, C.-A. and Taira, K. (2019) Resolvent-analysis-based design of airfoil separation control. Journal of Fluid Mechanics, 867:572–610.
- Discipline:
- Science and Engineering
-
- Creator:
- Moniri, Saman and Shahani, Ashwin J.
- Description:
- The data is comprised of 20 .hdf files of the X-ray projections recorded during isothermal annealing of Zn-Mg samples, at discrete time-steps shown below for files names ending in ‘...30141’ to ‘…30161’: 30141: prior to annealing; 30142: 1 min annealing; 30143: 3 min; 30144: 5 min; 30145: 7 min; 30146: 10 min; 30147: 15 min; 30148: 20 min; 30150: 31 min; 30151: 1 hr; 30152: 2 hr; 30153: 3 hr; 30154: 4 hr; 30155: 5 hr; 30156: 6 hr; 30157:7 hr; 30158: 8 hr; 30159:9 hr; 30160: 9 hr, 10 min; 30161: 10 hr The raw data file is in .hdf format and can be reconstructed into .tiff, e.g., by using the TomoPy toolbox in Python.
- Keyword:
- Spiral eutectics
- Discipline:
- Engineering
-
- Creator:
- Jones, Monica L.H.
- Description:
- These manikins represent body shape models for children weighing 9 to 23 kg in a seated posture relevant to child restraint design. The design of child restraints is guided in part by anthropometric data describing the distributions of body dimensions of children. However, three-dimensional body shape data have not been available for children younger than three years of age. These manikins will be useful for assessing child accommodation in restraints. The SBSM can also provide guidance for the development of anthropomorphic test devices and computational models of child occupants. The sampled manikins were predicted for a range of torso length and body weight dimensions. The SBSM model was exercised for two torso lengths and nine body weights to obtain 18 body shapes. The 3D shape models can be downloaded in a standard mesh format (PLY). Each body shape is accompanied by predicted landmark locations and standard anthropometric variables.
- Keyword:
- Child anthropometry, Child restraint system, Statistical body shape model, and Anthropomorphic testing device (ATD)
- Discipline:
- Engineering
-
- Creator:
- Carlevaris-Bianco, Nicholas , Ushani, Arash , and Eustice, Ryan
- Description:
- This is a large scale, long-term autonomy dataset for robotics research collected on the University of Michigan’s North Campus. The dataset consists of omnidirectional imagery, 3D lidar, planar lidar, GPS, and proprioceptive sensors for odometry collected using a Segway robot. The dataset was collected to facilitate research focusing on longterm autonomous operation in changing environments. The dataset is comprised of 27 sessions spaced approximately biweekly over the course of 15 months. The sessions repeatedly explore the campus, both indoors and outdoors, on varying trajectories, and at different times of the day across all four seasons. This allows the dataset to capture many challenging elements including: moving obstacles (e.g., pedestrians, bicyclists, and cars), changing lighting, varying viewpoint, seasonal and weather changes (e.g., falling leaves and snow), and long-term structural changes caused by construction projects. To further facilitate research, we also provide ground-truth pose for all sessions in a single frame of reference. and A detailed description of the dataset and the methods used to generate it is in the document nclt.pdf. If you use this dataset in your research please cite: Carlevaris-Bianco, N., Ushani, A., Eustice, R. (2021). The University of Michigan North Campus Long-Term Vision and LIDAR Dataset [Data set]. University of Michigan - Deep Blue. https://doi.org/10.7302/7rnm-6a03
- Keyword:
- Long-term SLAM, place recognition, lidar, computer vision, and field and service robotics
- Citation to related publication:
- Carlevaris-Bianco, Nicholas, et al. “University of Michigan North Campus Long-Term Vision and Lidar Dataset.” The International Journal of Robotics Research, vol. 35, no. 9, Aug. 2016, pp. 1023–1035, doi:10.1177/0278364915614638.
- Discipline:
- Engineering
-
- Creator:
- Malik, Hafiz and Khan, Muhammad Khurran, King Saud University
- Description:
- Details of the microphone used for data collection, acoustic environment in which data was collected, and naming convention used are provided here. 1 - Microphones Used: The microphones used to collect this dataset belong to 7 different trademarks. Table (1) illustrates the number of used Mics of different trademarks and models. Table 1: Trademarks and models of Mics Mic Trademark Mic Model # of Mics Shure SM-58 3 Electro-Voice RE-20 2 Sennheiser MD-421 3 AKG C 451 2 AKG C 3000 B 2 Neumann KM184 2 Coles 4038 2 The t.bone MB88U 6 Total 22 2- Environment Description: A brief description of the 6 environments in which the dataset was collected is presented here: (i) Soundproof room: a small room (nearly 1.5m × 1.5m × 2m), which is closed and completely isolated. With an exception of a small window in the front side of the room which is made of glass, all the walls of the room are made of wood and covered by a layer of sponge from the inner side, and the floor is covered by carpet. (ii) Class room: standard class room (6m × 5m × 3m). (iii) Lab: small lab (4m × 4m × 3m). All the walls are made of glasses and the floor is covered by carpet. The lab contains 9 computers. (iv) Stairs: is in the second floor. The place of recording is 3m × 5m (v) Parking: is the college parking. (vi) Garden: is an open space outside the buildings. 3- Naming Convention: This set of rules were followed as a naming convention to give each file in the dataset a unique name: (i) The file name is 19 characters long, and consists of 5 sections separated by underscores. (ii) The first section is of 3 characters indicates the Microphone trademark. (iii) The second section of 4 characters indicates the microphone model as in table (2). (iv) The third section of 2 characters indicates a specific microphone within a set of microphones of the same trademark and model, since we have more than one microphone of the same trademark and model. (v) The fourth section of 2 characters indicates the environment, where Soundproof room --> 01 Class room --> 02 Lab --> 03 Stairs --> 04 Parking --> 05 Garden --> 06 (vi) The fifth section of 2 characters indicates the language, where Arabic --> 01 English --> 02 Chinese --> 03 Indonesian --> 04 (vii) The sixth section of 2 characters indicates the speaker. Table 2: Microphones Naming Criteria Original Mic Trademark and model --> Naming Convenient Shure SM-58 --> SHU_0058 Electro-Voice RE-20 --> ELE_0020 Sennheiser MD-421 --> SEN_0421 AKG C 451 --> AKG_0451 AKG C 3000 B --> AKG_3000 Neumann KM184 --> NEU_0184 Coles 4038 --> COL_4038 The t.bone MB88U --> TBO_0088 For example: SEN_0421_02_01_02_03 is an English file recorded by speaker number 3 in the soundproof room using microphone number 2 of Sennheiser MD-421
- Keyword:
- audio forensic, multimedia forensics, microphone identification, tamper detection, splicing detection, and codec identification
- Citation to related publication:
- Muhammad Khurram Khan, Mohammed Zakariah, Hafiz Malik & Kim-Kwang Raymond Choo (2018). A novel audio forensic data-set for digital multimedia forensics, Australian Journal of Forensic Sciences, 50:5, 525-542, http://dx.doi.org/10.1080/00450618.2017.1296186
- Discipline:
- Engineering, Government, Politics and Law, and Science
-
- Creator:
- Pine, Alexandra F and Love, Brian J
- Description:
- This data is from a project concerned with dehydrating samples of saturated superabsorbent polymer using a centrifuge. The goal was to consider centrifugation as an energy efficient scheme to dehydrate SAP with the notion of reusing it. The data provided contains mass fractions of solvent removed through centrifugation with varied parameters.
- Keyword:
- Superabsorbent Polymer
- Citation to related publication:
- Pine, A., Wu, C. C., Raghavan, S., & Love, B. (2021). The efficiency of dehydrating desiccants by centrifugation: An assessment of superabsorbent polymers. Drying Technology, 0(0), 1–8. https://doi.org/10.1080/07373937.2021.1939710
- Discipline:
- Engineering
-
- Creator:
- Sick, Volker , Reuss, David L, and Greene, Mark L
- Description:
- This archive contains data files from spark-ignited homogeneous combustion internal combustion engine experiments. Included are high-resolution two-dimensional two-component velocity fields acquired at two 5 x 6 mm regions, one near the head and one near the piston. Crank angle resolved heat flux measurements were made at a third location in the head. The engine was operated at 40 kPa, 500 and 1300 RPM, motor and fired. Included are in-cylinder pressure measurements, external pressure and temperature data, as well as details on the geometry of the optical engine to enable setups of simulation configurations.
- Keyword:
- combustion, internal combustion engine, heat Transfer, particle image velocimetry, in-cylinder flow, TCC III engine , optical engine, CFD validation, PIV, boundary layer, and turbulence
- Discipline:
- Engineering
-
- Creator:
- Schiffmann, Philipp, Sick, Volker, and Reuss, David L
- Description:
- This archive contains data files from motored internal combustion engine experiments. Included are two-dimensional two-component velocity fields from four measurement planes with maximized field of view. in-cylinder pressure measurements, external pressure and temperature data, as well as details on the geometry of the optical engine to enable setups of simulation configurations. Motored operating conditions include 40kPa and 90kPa MAP, 800 and 1300 RPM.
- Keyword:
- TCC III engine, internal combustion engine, particle image velocimetry, in-cylinder flow, turbulence in engines, CFD validation data, motored engine, optical engine, cyclic variability , and PIV
- Citation to related publication:
- http://dx.doi.org/10.2516/ogst/2015028
- Discipline:
- Engineering
-
- Creator:
- Schiffmann, Philipp, Sick, Volker, and Reuss, David L
- Description:
- This archive contains data files from spark-ignited homogenous combustion internal combustion engine experiments. Included are two-dimensional two-component velocity fields acquired in a small, high-resolution field of view near the spark plug, and images of hydroxyl radical chemiluminescence recording the early flame-kernel growth. Included are in-cylinder pressure measurements, external pressure and temperature data, as well as details on the geometry of the optical engine to enable setups of simulation configurations. Included are tables of one-per-cycle parameters for each test with methane or propane at stoichiometric, dilute limit, lean limit, and rich limit, operation conducted at 40kPa and 1300 RPM.
- Keyword:
- OH* imaging, TCC III engine, internal combustion engine, particle image velocimetry, in-cylinder flow, turbulence in engines, CFD validation data, cyclic variability, early flame kernel growth, optical engine, combustion variability, ignition, and PIV
- Citation to related publication:
- dx.doi.org/10.1177/1468087417720558
- Discipline:
- Engineering
-
- Creator:
- Schiffmann, Philipp, Sick, Volker, and Reuss, David L
- Description:
- This archive contains data files from spark-ignited homogenous combustion internal combustion engine experiments. Included are two-dimensional two-component velocity fields from various measurement planes with maximized field of view, in-cylinder pressure measurements, external pressure and temperature data, as well as details on the geometry of the optical engine to enable setups of simulation configurations. Fired operation was with stoichiometric propane air, 40kPa MAP, at 1300 RPM.
- Keyword:
- TCC III engine, internal combustion engine, particle image velocimetry, in-cylinder flow, turbulence in engines, CFD validation data, cyclic variability, optical engine, combustion variability, and PIV
- Citation to related publication:
- dx.doi.org/10.1177/1468087417720558
- Discipline:
- Engineering
-
- Creator:
- Klinich, Kathleen D, Lin, Brian, and Moore, Jamie L.
- Description:
- This dataset allows comparison of the different strategies implemented by vehicle manufacturers being used to communicate with drivers. Spreadsheets were created in MS Excel to summarize data for each vehicle, and include page numbers in each vehicle owner's manual for reference. The photos taken of each vehicle control panel allow detailed inspection of the displays and controls.
- Keyword:
- vehicle, controls, displays, and FMVSS 101
- Discipline:
- Engineering
-
- Creator:
- Gliske, Stephen V and Stacey, William C
- Description:
- This data is part of a large program to translate detection and interpretation of HFOs into clinical use. A zip file is included which contains hfo detections, metadata, and Matlab scripts. The matlab scripts analyze this input data and produce figures as in the referenced paper (note: the blind source separation method is stochastic, and so the figures may not be exactly the same). A file "README.txt" provides more detail about each individual file within the zip file.
- Keyword:
- hfo, high frequency oscillation, ripple, fast ripple, blind source separation, non-negative matrix factorization, and temporal variability
- Discipline:
- Science, Engineering, and Health Sciences
-
- Creator:
- Gliske, Stephen V and Stacey, William C
- Description:
- This data repository includes the quantitative features of high frequency, intracranial EEG along with all necessary scripts to reproduce the figures of the accompanying manuscript.
- Keyword:
- high frequency oscillation, HFO, high frequency activity, and epilepsy
- Citation to related publication:
- (under review)
- Discipline:
- Science, Engineering, and Health Sciences
-
- Creator:
- Sugrue, Dennis P.
- Description:
- Our work seeks to better understand the financial risks to corporate operations as a basis for exploring alternative public-private investment strategies. We applied network analysis to model financial relationships within this sector and its connectedness to primary commodities transported on the Great Lakes. The financial network maps were used to quantitatively analyze the industry risk exposure using corporate financial metrics and to query the financial interdependencies of companies relative to the Great Lakes waterway. Results demonstrate that inventory turnover ratio is a robust proxy to quantify weighted financial risks of water dependency across the entire supply chain network. All data was manually collected from the Bloomberg Terminal and FactSet which are licensed by the University of Michigan. The SPLC module in the Terminal restricts data download and information must be captured manually. All data was collected from September-November 2018.
- Keyword:
- Iron Ore, Supply Chain, Bloomberg Terminal, and Great Lakes
- Citation to related publication:
- Sugrue, Dennis, Abigail Martin, and Peter Adriaens. (under review). “Financial Network Analysis to Inform Infrastructure Investment: Great Lakes Waterway and the Steel Supply Chain.” Journal of Infrastructure Systems, American Society of Civil Engineers.
- Discipline:
- Engineering
-
- Creator:
- Huffaker, Jordan S., Kummerfeld, Jonathan K., Lasecki, Walter S., and Ackerman, Mark S.
- Description:
- The following files include supplementary materials for our CHI 2020 paper "Crowdsourced Detection of Emotionally Manipulative Language". Namely, these materials include the dataset that was used in the evaluation. See the paper for more details.
- Keyword:
- Crowdsourcing, Media Manipulation, Rhetoric, and Emotion
- Citation to related publication:
- J.S. Huffaker, J.K. Kummerfeld, W.S. Lasecki, M.S. Ackerman. Crowdsourced Detection of Emotionally Manipulative Language. In Proceedings of the ACM Conference on Human Factors in Computing Systems (CHI 2020). Honolulu, HI. 2020.
- Discipline:
- Engineering
-
- Creator:
- Brandt, Daniel, A. and Ridley, Aaron, J.
- Description:
- The research that produced this data focused on conducting a statistical comparison between horizontal winds modeled with GITM and those derived from the accelerometer aboard the GOCE satellite. The winds from GITM and GOCE were compared by constructing their respective probability densities under different levels of geomagnetic activity, and by distributing them as a function of geomagnetic activity, magnetic latitude, magnetic local time, day-of-the-year, and solar radio flux.
- Keyword:
- Thermosphere, GITM, GOCE, Neutral winds, and Thermospheric modeling
- Discipline:
- Science and Engineering
-
- Creator:
- Larson, Ronald G., Wen, Fei, Huang, Wenjun, and Huang, Ming
- Description:
- We provide the parameters used in Umbrella Sampling simulations reported in our study "Efficient Estimation of Binding Free Energies between Peptides and an MHC Class II Molecule Using Coarse-Grained Molecular Dynamics Simulations with a Weighted Histogram Analysis Method", namely the set positions and spring constants for each window in simulations. Two tables are provided. Table 1 lists the names of the peptides and their corresponding sequences. Table 2 lists the parameters. The abstract of our work is the following: We estimate the binding free energy between peptides and an MHC class II molecule using molecular dynamics (MD) simulations with Weighted Histogram Analysis Method (WHAM). We show that, owing to its more thorough sampling in the available computational time, the binding free energy obtained by pulling the whole peptide using a coarse-grained (CG) force field (MARTINI) is less prone to significant error induced by biased-sampling than using an atomistic force field (AMBER). We further demonstrate that using CG MD to pull 3-4 residue peptide segments while leaving the remain-ing peptide segments in the binding groove and adding up the binding free energies of all peptide segments gives robust binding free energy estimations, which are in good agreement with the experimentally measured binding affinities for the peptide sequences studied. Our approach thus provides a promising and computationally efficient way to rapidly and relia-bly estimate the binding free energy between an arbitrary peptide and an MHC class II molecule.
- Keyword:
- Molecular Dynamics, Binding Free Energy, Protein, MHC, and Coarse-Grained
- Discipline:
- Science and Engineering
-
- Creator:
- Ramasubramani, Vyas
- Description:
- The goal of the work is to elucidate the stability of a complex experimentally observed structure of proteins. We found that supercharged GFP molecules spontaneously assemble into a complex 16-mer structure that we term a protomer, and that under the right conditions an even larger assembly is observed. The protomer structure is very well defined, and we performed simulations to try and understand the mechanics underlying its behavior. In particular, we focused on understanding the role of electrostatics in this system and how varying salt concentrations would alter the stability of the structure, with the ultimate goal of predicting the effects of various mutations on the stability of the structure. There are two separate projects included in this repository, but the two are closely linked. One, the candidate_structures folder, contains the atomistic outputs used to generate coarse-grained configurations. The actual coarse-grained simulations are in the rigid_protein folder, which pulls the atomistic coordinates from the other folder. All data is managed by signac and lives in the workspace directories, which contain various folders corresponding to different parameter combinations. The parameters associated with a given folder are stored in the signac_statepoint.json files within each subdirectory. The atomistic data uses experimentally determined protein structures as a starting point; all of these are stored in the ConfigFiles folder. The primary output is the topology files generated from the PDBs by GROMACS; these topologies are then used to parametrize the Monte Carlo simulations. In some cases, atomistic simulations were actually run as well, and the outputs are stored alongside the topology files. In the rigid_protein folder, the ConfigFiles folder contains MSMS, the software used to generate polyhedral representations of proteins from the PDBs in the candidate_structures folder. All of the actual polyhedral structures are also stored in the ConfigFiles folder. The actual simulation trajectories are stored as general simulation data (GSD) files within each subdirectory of the workspace, along with a single .pos file that contains the shape definition of the (nonconvex) polyhedron used to represent a protein. The logged quantities, such as energies and MC move sizes, are stored in .log files. The logic for the simulations in the candidate_structures project is in the Python scripts project.py, operations.py, and scripts/init.py. The rigid_protein folder also includes the notebooks directory, which contains Jupyter notebooks used to perform analyses, as well as the Python scripts used to actually perform the simulations and manage the data space. In particular, the project.py, operations.py and scripts/init.py scripts contain most of the logic associated with the simulations.
- Keyword:
- Protein assembly, Cryo TEM, Hierarchical Assembly, Monte Carlo simulation, and Coarse-grained simulation
- Discipline:
- Science and Engineering
-
- Creator:
- Limon, Garrett C.
- Description:
- The data represents weekly output from three 60-year CAM6 model runs. The output includes state (.h0. files) and tendency (.h1. files) fields for three difference model configurations of increasing complexity. State fields include temperature, surface pressure, specific humidity, among others; while tendencies include temperature tendencies, specific humidity tendencies, as well as precipitation rates. Using the state variables at a given time step, machine learning techniques can be trained to predict the following tendency field, which can then be applied to the state variables to provide the state at the next physics time step of the model.
- Keyword:
- Machine Learning, Climate Modeling, and Physics Emulation
- Citation to related publication:
- Limon, G. C., Jablonowski, C. (2022) Probing the Skill of Random Forest Emulators for Physical Parameterizations via a Hierarchy of Simple CAM6 Configurations [Preprint]. ESSOAr. https://10.1002/essoar.10512353.1
- Discipline:
- Engineering and Science
-
- Creator:
- Limon, Garrett C.
- Description:
- The work guides the processing of CAM6 data for use in machine learning applications. We also provide workflow scripts for training both random forests and neural networks to emulate physic s schemes from the data, as well as analysis scripts written in both Python and NCL in order to process our results.
- Keyword:
- Machine Learning, Climate Modeling, and Physics Emulation
- Citation to related publication:
- Limon, G. C., Jablonowski, C. (2022) Probing the Skill of Random Forest Emulators for Physical Parameterizations via a Hierarchy of Simple CAM6 Configurations [Pre Print]. ESSOAr. https://10.1002/essoar.10512353.1
- Discipline:
- Engineering and Science
-
- Creator:
- Regoli, Leonardo H.
- Description:
- The research analyzed the response of nine PNI RM3100 magnetometers to radiation doses expected during a Europa lander mission. The radiation levels are drawn from the Europa Lander Science Definition Team report ( https://europa.nasa.gov/resources/58/europa-lander-study-2016-report). The sensors were tested up to a total ionization dose (TID) level of 500 kRad.
- Keyword:
- Magnetometer, Magneto-inductive, Europa, and Radiation
- Citation to related publication:
- Regoli, L. H., Moldwin, M. B., Raines, C., Nordheim, T. A., Miller, C. A., Carts, M., and Pozzi, S. A.: Radiation tolerance of the PNI RM3100 magnetometer for a Europa lander mission, Geosci. Instrum. Method. Data Syst., 9, 499–507, https://doi.org/10.5194/gi-9-499-2020, 2020.
- Discipline:
- Science and Engineering
-
- Creator:
- Grosky, William I. and Ruas, Terry L.
- Description:
- This dataset was used for a proof-of-concept of fixed lexical chain approach for semantic information retrieval.
- Keyword:
- fixed lexical chains
- Citation to related publication:
- Ruas, T. L., & Grosky, W. I. (2017). Exploring and expanding the use of lexical chains in information retrieval. Ann Arbor: University of Michigan. Retrieved from the Deep Blue institutional repository website: http://dx.doi.org/10.3998/2027.42/136659
- Discipline:
- Engineering
-
- Creator:
- James, David A. and Lokam, Nikhil
- Description:
- The object of this project is to provide researchers and students with a tool to allow them to develop an intuitive understanding of singular vectors and singular values. 2x2 matrices A with real entries map circles to ellipses; in particular, unit circles centered at the origin to ellipses centered at the origin. It is known that the points on the ellipse farthest from the origin correspond to the singular vectors of A. Users can use the GUI to enter matrices of their choice and explore to visually self-determine the singular vectors/values.
- Keyword:
- SVD, Singular Value Decomposition, Singular Vector, Singular Value, and Matrix
- Discipline:
- Science and Engineering
-
- Creator:
- Jivani, Aniket, Sachdeva, Nishtha, Huang, Zhenguang, Chen, Yang, van der Holst, Bart, Manchester, Ward, Iong, Daniel, Chen, Hongfan, Zou, Shasha, Huan, Xun, and Toth, Gabor
- Description:
- In this work, we perform Global Sensitivity Analysis (GSA) for the background solar wind in order to quantify contributions from uncertainty of different model parameters to the variability of in-situ solar wind speed and density at 1au, both of which have a major impact on CME propagation and strength. Scripts written in the Julia language are used to build the PCE and calculate the sensitivity results. Data is available in csv, NetCDF and JLD files. A `Project.toml` file is included to activate and install all required dependencies (See README for details).
- Keyword:
- Uncertainty Quantification, Space Weather, and Global Sensitivity Analysis
- Discipline:
- Engineering
-
Resources for Training Machine Learning Algorithms Using CAM6 Simple Physics Packages
User Collection- Creator:
- Limon, Garrett
- Description:
- The collection contains the code and the data used to train machine learning algorithms to emulate simplified physical parameterizations within the Community Atmosphere Model (CAM6). CAM6 is the atmospheric general circulation model (GCM) within the Community Earth System Model (CESM) framework, developed by the National Center for Atmospheric Research (NCAR). GCMs are made up of a dynamical core, responsible for the geophysical fluid flow calculations, and physical parameterization schemes, which estimate various unresolved processes. Simple physics schemes were used to train both random forests and neural networks in the interest of exploring the feasibility of machine learning techniques being used in conjunction with the dynamical core for improved efficiency of future climate and weather models. The results of the research show that various physical forcing tendencies and precipitation rates can be effectively emulated by the machine learning models.
- Keyword:
- Machine Learning, Climate Modeling, and Physics Emulators
- Discipline:
- Science and Engineering
2Works -
- Creator:
- Hall, Ryan J. and Larson, Ronald G.
- Description:
- This is data is a large assortment of over 50 1,4-polybutadiene star-linear blends that can be used for assessing and developing predictive models. The data are presented in CSV files.
- Keyword:
- polymers, rheology, star-linear polymer blends, and shear rheology
- Citation to related publication:
- Hall, R., Desai, P. S., Kang, B.-G., Huang, Q., Lee, S., Chang, T., Venerus, D. C., Mays, J., Ntetsikas, K., Polymeropoulos, G., Hadjichristidis, N., & Larson, R. G. (2019). Assessing the Range of Validity of Current Tube Models through Analysis of a Comprehensive Set of Star–Linear 1,4-Polybutadiene Polymer Blends. Macromolecules, 52(20), 7831–7846. https://doi.org/10.1021/acs.macromol.9b00642
- Discipline:
- Science and Engineering
-
- 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:
- Thompson, Ellen P. and Ellis, Brian R.
- Description:
- Accurate prediction of physical alterations in carbonate reservoirs under dissolution is critical for development of subsurface energy technologies. The impact of mineral dissolution on flow characteristics depends on the connectivity and tortuosity of the pore network. Persistent homology is a tool from algebraic topology that describes the size and connectivity of topological features. When applied to 3D X-ray computed tomography (XCT) imagery of rock cores, it provides a novel metric of pore network heterogeneity. Prior works have demonstrated the efficacy of persistent homology in predicting flow properties in numerical simulations of flow through porous media. Its ability to combine size, spatial distribution, and connectivity information make it a promising tool for understanding reactive transport in complex pore networks, yet limited work has been done to apply persistence analysis to experimental studies on natural rocks. In this study, three limestone cores were imaged by XCT before and after acid-driven dissolution flow through experiments. Each XCT scan was analyzed using persistent homology. In all three rocks, permeability increase was driven by the growth of large, connected pore bodies. The two most homogenous samples saw an increased effect nearer to the flow inlet, suggesting emerging preferential flow paths as the reaction front progresses. The most heterogeneous sample showed an increase in along-core homogeneity during reaction. Variability of persistence showed moderate positive correlation with pore body size increase. Persistence heterogeneity analysis could be used to anticipate where greatest pore size evolution may occur in a reservoir targeted for subsurface development, improving confidence in project viability.
- Keyword:
- Carbonate dissolution, X-ray computed tomography, Porous media, Topology, and Persistent homology
- Citation to related publication:
- Thompson, E.P.; Ellis, B.R. (2023) Persistent Homology as a Heterogeneity Metric for Predicting Pore Size Change in Dissolving Carbonates. In Review.
- Discipline:
- Science and Engineering
-
- Creator:
- Szuromi, Matthew P. and Stacey, William C.
- Description:
- The data and scripts are meant to show how burster dynamics determine response to a single biphasic stimulus. The files include data which show trends in the propensity of termination for different burster types and the MATLAB scripts used to generate this data. The MATLAB scripts also allow the user to generate their own data sets for alternative bursting paths and stimulus parameter combinations. Furthermore, they allow the user to visually examine the effects of single stimuli in the voltage timeseries and in state space. How the user can access these features of the script is described in the file "ReadMe.pdf."
- Keyword:
- Epilepsy, Stimulation, Modelling, Dynamics, Seizure, and Dynamotype
- Citation to related publication:
- (PROVISIONAL) Optimization of Ictal Aborting Stimulation Using the Dynamotype Taxonomy
- Discipline:
- Health Sciences, Engineering, and Science
-
- Creator:
- Shah, Bhavarth
- Description:
- The three approaches used three distinct datasets named as follows: Historicalwater_levels.csv, Historical_Precipitation.csv, and Bayesian Statistical dataset.csv. These files are accessible using Microsoft Office or similar software. The machine learning models are developed in Jupyter Notebook (.ipynb) files, named according to the datasets they utilize. However, for the third approach, the models are named Random Forest, LSTM Model Base, and Multivariate LSTM Models. More details are available on the Shah_Bhavarth_Readme.txt. These notebooks can be accessed through Python, Project Jupyter, or Google Colab, and dependencies include libraries such as Pandas, NumPy, Matplotlib, Scikit-learn, Keras, and TensorFlow. The supplementary material also includes Excel files for stage-curve calculations and diversions, named Water_levels_Stage_Curve_Calculations1970-2018.xlsx and Diversions_calculation.xlsx, respectively.
- Keyword:
- Machine learning, Forecasting, Water levels, Mono lake, and Hydrology
- Citation to related publication:
- Shah, Bhavarth. 2024. "Mono Lake Water Levels Forecasting Using Machine Learning." Master’s thesis, University of Michigan, School for Environment and Sustainability. ORCID iD: 0000-0002-2391-8610. https://dx.doi.org/10.7302/22659
- Discipline:
- Science and Engineering
-
- Creator:
- Elvati, Paolo, Luyet, Chloe, Wang, Yichun, Liu, Changjiang, VanEpps, J. Scott, Kotov, Nicholas A., and Violi, Angela
- Description:
- Amyloid nanofibers are abundant in microorganisms and are integral components of many biofilms, serving various purposes, from virulent to structural. Nonetheless, the precise characterization of bacterial amyloid nanofibers has been elusive, with incomplete and contradicting results. The present work focuses on the molecular details and characteristics of PSMa1-derived functional amyloids present in Staphylococcus aureus biofilms, using a combination of computational and experimental techniques, to develop a model that can aid the design of compounds to control amyloid formation. Results from molecular dynamics simulations, guided and supported by spectroscopy and microscopy, show that PSMa1 amyloid nanofibers present a helical structure formed by two protofilaments, have an average diameter of about 12 nm, and adopt a left-handed helicity with a periodicity of approximately 72 nm. The chirality of the self-assembled nanofibers, an intrinsic geometric property of its constituent peptides, is central to determining the fibers' lateral growth.
- Keyword:
- molecular self-assembly, computational nanotechnology, nanobiotechnology, and structural properties
- Citation to related publication:
- Paolo Elvati, Chloe Luyet, Yichun Wang, Changjiang Liu, J. Scott VanEpps, Nicholas A. Kotov, and Angela Violi ACS Applied Nano Materials 2023 6 (8), 6594-6604 DOI: 10.1021/acsanm.3c00174
- Discipline:
- Engineering and Science
-
- Creator:
- Tsai, Grace and Kuipers, Benjamin
- Description:
- ******Michigan Indoor Corridor 2012 Dataset****** This dataset is made available for research purpose only. Please contact Grace Tsai( gstsai@umich.edu) for any questions or comments. This dataset was used to produce the results in our IROS 2012 paper. If you use the data, please cite the following reference in your publications related to this work: Grace Tsai and Benjamin Kuipers Dynamic Visual Understanding of the Local Environment for an Indoor Navigating Robot International Conference on Intelligent Robots and Systems (IROS'12) October 2012 The dataset contains 4 video sequences acquired with camera mounted on a wheeled vehicle. The camera was set-up so that there was zero tilt and roll angle with respect to the ground. The camera has a fixed height (0.47 m) with the ground throughout the video. The intrinsic parameters of the cameras are: Focal length fc = [ 1389.182714 1394.598277 ] Principal point cc = [ 672.605430 387.235803 ] The distortion of the camera has been corrected. For each video sequences, an estimated camera pose in each frame of the video is provided in the file pose.txt. Each line in the file looks like: <frame index> <x (pose)> <y (pose)> <theta (pose)> Note the camera poses provided here are estimated by using an occupancy grid mapping algorithm with a laser range finder to obtain the robot pose. The dataset provides a ground truth labeling for all the pixels every 10 frames for each video. The labels of each frame is stored as a 2D matrix in a .mat file. The filename of each .mat file corresponds to the image frame. The labels can be interpreted as followed: -2 -> ceiling plane -1 -> ground plane >0 -> walls The labels of the walls are illustrated in a .pdf figure. Note the figure is only a illustration graph, not an actual floor plan.
- Keyword:
- Robotics and Computer vision
- Discipline:
- Engineering
-
- 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:
- Bougher, S. W. (CLaSP Department, U. of Michigan), Roeten, K. J. (CLaSP Department, U. of Michigan), and Sharrar, R. (Astronomy Department, U. of Michigan)
- Description:
- The NASA MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft, which is currently in orbit around Mars, has been taking daily (systematic) measurements of the densities and temperatures in the upper atmosphere of Mars between about 140 to 240 km above the surface. Wind measurement campaigns are also conducted once per month for 5-10 orbits. These densities, temperatures and winds change with time (e.g. season, local time) and location, and sometimes fluctuate quickly. Global dust storm events are also known to significantly impact these density, temperature and wind fields in the Mars thermosphere. Such global dust storm period measurements can be compared to simulations from a computer model of the Mars atmosphere called M-GITM (Mars Global Ionosphere-Thermosphere Model), developed at U. of Michigan. This is the first detailed comparison between direct global dust storm period measurements in the upper atmosphere of Mars and simulated MGITM fields and is important because it can help to inform us what physical processes are acting on the upper atmosphere during such large dust events. Since the global circulation plays a role in the structure, variability, and evolution of the atmosphere, understanding the processes that drive the winds in the upper atmosphere of Mars also provides key context for understanding how the atmosphere behaves as a whole system. A basic version of the M-GITM code can be found on Github as follows: https:/github.com/dpawlows/MGITM and About 4 months of Neutral Gas and Ion Mass Spectrometer (NGIMS) measurements of densities and winds have been made by the MAVEN team during the summer of 2018 (Elrod et al., 2019). Nine reference measurement intervals during this global dust storm (1-June through 30-August 2018) are selected for detailed study (Elrod et al. 2019). The Mars conditions for these nine intervals have been used to launch corresponding M-GITM code simulations, yielding 3-D neutral density, temperature and wind fields for comparison to these NGIMS measurements. The M-GITM datacubes used to extract the density, temperature and neutral winds, along the trajectory of each orbit path between 140 and 240 km, are provided in this Deep Blue Data archive. README files are provided for each datacube, detailing the contents of each file. A general README file is also provided that summarizes the inputs and outputs of the M-GITM code simulations for this study.
- Keyword:
- Mars, MAVEN Spacecraft, Mars Thermosphere, and Mars Global Dust Storm of 2018
- Citation to related publication:
- Elrod, M. K., S. W. Bougher, K. Roeten, R. Sharrar, J. Murphy, Structural and Compositional Changes in the Upper Atmosphere related to the PEDE-2018 Dust Event on Mars as Observed by MAVEN NGIMS, Geophys. Res. Lett., (2019). doi: 10.1029/2019GL084378. and Jain, S. K., Bougher, S. W., Deighan, J., Schneider, N. M., Gonzalez‐Galindo, F., Stewart, A. I. F., et al. ( 2020). Martian thermospheric warming associated with the Planet Encircling Dust Event of 2018. Geophysical Research Letters, 47, e2019GL085302. https://doi.org/10.1029/2019GL085302
- Discipline:
- Engineering and Science
-
- Creator:
- Bougher, Stephen W. (CLaSP Department, U. of Michigan) and Roeten, Kali J. (CLaSP Department, U. of Michigan)
- Description:
- The NASA MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft, which is currently in orbit around Mars, has been taking monthly measurements of the speed and direction of the winds in the upper atmosphere of Mars between about 140 to 240 km above the surface. The observed wind speeds and directions change with time and location, and sometimes fluctuate quickly. These measurements are compared to simulations from a computer model of the Mars atmosphere called M-GITM (Mars Global Ionosphere-Thermosphere Model), developed at U. of Michigan. This is the first comparison between direct measurements of the winds in the upper atmosphere of Mars and simulated winds and is important because it can help to inform us what physical processes are acting on the observed winds. Some wind measurements have similar wind speeds or directions to those predicted by the M-GITM model, but sometimes, there are large differences between the simulated and measured winds. The disagreements between wind observations and model simulations suggest that processes other than normal solar forcing may become relatively more important during these observations and alter the expected circulation pattern. Since the global circulation plays a role in the structure, variability, and evolution of the atmosphere, understanding the processes that drive the winds in the upper atmosphere of Mars provides key context for understanding how the atmosphere behaves as a whole system. A basic version of the M-GITM code can be found on Github as follows: https:/github.com/dpawlows/MGITM and About 30 Neutral Gas and Ion Mass Spectrometer (NGIMS) wind campaigns (of 5 to 10 orbits each) have been conducted by the MAVEN team (Benna et al., 2019). Five of these campaigns are selected for detailed study (Roeten et al. 2019). The Mars conditions for these five campaigns have been used to launch corresponding M-GITM code simulations, yielding 3-D neutral wind fields for comparison to these NGIMS wind observations. The M-GITM datacubes used to extract the zonal and meridional neutral winds, along the trajectory of each orbit path between 140 and 240 km, are provided in this Deep Blue Data archive. README files are provided for each datacube, detailing the contents of each file. A general README file is also provided that summarizes the inputs and outputs of the M-GITM code simulations for this study.
- Keyword:
- Mars, MAVEN spacecraft, Mars thermosphere, and Mars global upper atmosphere winds
- Citation to related publication:
- Roeten, K. J., Bougher, S. W., Benna, M., Mahaffy, P. R., Lee, Y., Pawlowski, D., et al. (2019). MAVEN/NGIMS thermospheric neutral wind observations: Interpretation using the M‐GITM general circulation model. Journal of Geophysical Research: Planets, 124, 3283– 3303. https://doi.org/10.1029/2019JE005957
- Discipline:
- Science and Engineering
-
- Creator:
- Bougher, S. W. (CLaSP Department, University of Michigan)
- Description:
- The NASA MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft, which is currently in orbit around Mars, has been taking systematic measurements of the densities and deriving temperatures in the upper atmosphere of Mars between about 140 to 240 km above the surface since late 2014. Wind measurement campaigns are also conducted once per month for 5-10 orbits. These densities, temperatures and winds change with time (e.g. solar cycle, season, local time) and location, and sometimes fluctuate quickly. Global dust storm events are also known to significantly impact these density, temperature and wind fields in the Mars thermosphere. For the current project, the inert light species helium is used to trace the circulation patterns and constrain wind magnitudes throughout the Mars thermosphere. Presently, more than 6 years of Neutral Gas and Ion Mass Spectrometer (NGIMS) measurements of helium densities have been obtained by the MAVEN team (e.g. Elrod et al., 2017; 2021; Gupta et al., 2021). Measured helium distributions are compared to simulations from a computer model of the Mars atmosphere called M-GITM (Mars Global Ionosphere-Thermosphere Model), developed at U. of Michigan. Since the global circulation plays a role in the structure, variability, and evolution of the atmosphere, understanding the processes that drive the winds in the upper atmosphere of Mars also provides the needed context for understanding helium distributions and how the atmosphere behaves as a whole system. Three dimensional M-GITM simulations for the Mars four cardinal seasons (Ls = 0, 90, 180, 270, for Mars Year 33) were conducted for detailed comparisons with NGIMS helium and CO2 distributions (Gupta et al. 2021). The M-GITM datacubes used to extract these densities (plus winds) along the trajectory of each orbit path between 140 and 240 km, are provided in this Deep Blue Data archive. README files are also provided for each datacube, detailing the contents of each file. In addition, a general README file is provided that summarizes the inputs and outputs of the M-GITM code simulations for this study. Finally, a basic version of the M-GITM code can be found on Github at https:/github.com/dpawlows/MGITM.
- Keyword:
- Mars, MAVEN Spacecraft Mission, Mars Thermosphere, Helium Density Distributions, and Neutral Gas and Ion Mass Spectrometer (NGIMS)
- Citation to related publication:
- Gupta, N., N. V. Rao, S. W. Bougher, and M. K. Elrod, Latitudinal and Seasonal Asymmetries of the Helium Bulge in the Martian Upper Atmosphere J. Geophys. Res., 126, XXXX-XXXX. doi:10.1002/2021JEXXXXXX
- Discipline:
- Engineering and Science
-
- Creator:
- Luyet, Chloe, Elvati, Paolo, Vinh, Jordan, and Violi, Angela
- Description:
- A growing body of work has linked key biological activities to the mechanical properties of cellular membranes, and as a means of identification. Here, we present a computational approach to simulate and compare the vibrational spectra in the low-THz region for mammalian and bacterial membranes, investigating the effect of membrane asymmetry and composition, as well as the conserved frequencies of a specific cell. We find that asymmetry does not impact the vibrational spectra, and the impact of sterols depends on the mobility of the components of the membrane. We demonstrate that vibrational spectra can be used to distinguish between membranes and, therefore, could be used in identification of different organisms. The method presented, here, can be immediately extended to other biological structures (e.g., amyloid fibers, polysaccharides, and protein-ligand structures) in order to fingerprint and understand vibrations of numerous biologically-relevant nanoscale structures.
- Keyword:
- molecular dynamics, membranes, mechanical vibration, bacterial identification, and Staphylococcus aureus
- Citation to related publication:
- Luyet C, Elvati P, Vinh J, Violi A. Low-THz Vibrations of Biological Membranes. Membranes. 2023; 13(2):139. https://doi.org/10.3390/membranes13020139
- Discipline:
- Engineering
-
- Creator:
- Towne, Aaron and Dawson, Scott
- Description:
- This dataset contains data from direct numerical simulations of two-dimensional stationary and pitching flat-plate airfoils at Reynolds number 100. The dataset contains time-resolved snapshots of the velocity field, lift and drag coefficients, and airfoil kinematics spanning 40-100 convective time units. Cases include a stationary airfoil and eight different pitching frequencies. All data are stored within hdf5 files, and a Matlab script showing how the data can be read and manipulated is provided. Please see the ‘airfoilDNS_README.pdf’ file for more information. We recommend using the ‘airfoilDNS_example.zip’ file as an entry point to the dataset. and The dataset is part of “A database for reduced-complexity modeling of fluid flows” (see references below) and is intended to aid in the conception, training, demonstration, evaluation, and comparison of reduced-complexity models for fluid mechanics. The paper introduces the flow setup and computational methods, describes the available data, and provides an example of how these data can be used for reduced-complexity modeling. Users of these data should cite the papers listed below.
- Keyword:
- fluid mechanics and aerodynamics
- Citation to related publication:
- Towne, A., Dawson, S., Brès, G. A., Lozano-Durán, A., Saxton-Fox, T., Parthasarthy, A., Biler, H., Jones, A. R., Yeh, C.-A., Patel, H., Taira, K. (2022). A database for reduced-complexity modeling of fluid flows. AIAA Journal 61(7): 2867-2892. and Dawson, S. T. M., Floryan, D. C., Rowley, C. W., and Hemati, M. S. (2016) Lift enhancement of high angle of attack airfoils using periodic pitching. AIAA Paper 2016-2069.
- Discipline:
- Engineering and Science
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- Creator:
- Towne, Aaron, Jones, Anya, and Biler, Hulya
- Description:
- This dataset contains experimental measurements of a flat-plate airfoil passing through a large-amplitude transverse gust. The dataset contains an ensemble of of the airfoil-gust encounter to account for variability in the gust profile, and each realization contains time-resolved force measurements and planar PIV velocity fields. All data are stored within hdf5 files, and a Matlab script showing how the data can be read and manipulated is provided. Please see the ‘airfoilEXP_README.pdf’ file for more information. We recommend using the ‘airfoilEXP_example.zip’ file as an entry point to the dataset. and The dataset is part of “A database for reduced-complexity modeling of fluid flows” (see references below) and is intended to aid in the conception, training, demonstration, evaluation, and comparison of reduced-complexity models for fluid mechanics. The paper introduces the flow setup and computational methods, describes the available data, and provides an example of how these data can be used for reduced-complexity modeling. Users of these data should cite the papers listed below.
- Keyword:
- fluid mechanics and aerodynamics
- Citation to related publication:
- Towne, A., Dawson, S., Brès, G. A., Lozano-Durán, A., Saxton-Fox, T., Parthasarthy, A., Biler, H., Jones, A. R., Yeh, C.-A., Patel, H., Taira, K. (2022). A database for reduced-complexity modeling of fluid flows. AIAA Journal 61(7): 2867-2892., Biler, H., Sedky, G., Jones, A. R., Saritas, M. and Cetiner, O. (2021) Experimental investigation of transverse and vortex gust encounters at low Reynolds numbers. AIAA Journal, 59(3):786–799., and Andreu-Angulo, I., Babinsky, H., Biler, H., Sedky, G. and Jones, A. R. (2020) Effect of transverse gust velocity profiles. AIAA Journal, 58(12):5123–5133.
- Discipline:
- Science and Engineering