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- Creator:
- Ponder, Brandon M., Ridley, Aaron J., Goel, Ankit, and Bernstein, Dennis S.
- Description:
- This research was completed to statistically validate that a data-model refinement technique could integrate real measurements to remove bias from physics-based models via changing the forcing parameters such as the thermal conductivity coefficients.
- Keyword:
- Thermosphere, GITM, CHAMP, GRACE, MSIS, Upper Atmosphere Modeling, and Data Assimilation
- Citation to related publication:
- Ponder, B. M., Ridley, A. J., Goel, A., & Bernstein, D. S. (2023). Improving forecasting ability of GITM using data-driven model refinement. Space Weather, 21, e2022SW003290. https://doi.org/10.1029/2022SW003290
- Discipline:
- Engineering and Science
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Burkina Faso documentary videos
User Collection- Creator:
- Heath, Jeffrey G.
- Description:
- This is a collection of mostly short documentary-style videos related to linguistic fieldwork in southwestern Burkina Faso. The initial batch consists of videos produced in 2023, and others will be added. Versions of some of these videos overdubbed in native languages will also be produced for local consumption in Burkina. Most of the videos document everyday practical activities; some also feature useful native plants and insects. This collection is parallel to collections of videos from neighboring Mali: see "Central Mali documentary videos" (with documentaries produced up to 2018) and "Mali documentary videos from 2023 on" for the newer ones. A small collection from north-central Côte d'Ivoire is also in the works. Within each collection, the videos are organized into "works" based on the general type of activity documented.
- Keyword:
- Burkina Faso and documentary videos
- Discipline:
- Humanities
7Works -
Mali documentary videos from 2023
User Collection- Creator:
- Heath, Jeffrey G.
- Description:
- Each "work" in this collection is a set of documentary-style videos in mp4 (m4v) format. The initial (2023) set of works is as follows: "farming and plant gathering (Mali mp4)", "construction and boatbuilding (Mali mp4)", "fishing (Mali mp4)", "food and beverage preparation (Mali mp4)", metalwork and woodwork (Mali mp4)", "cultural events (Mali mp4)", "firearms and gunpowder (Mali mp4)", "pottery (Mali mp4)", and "weaving and dyeing (Mali mp4)". Funding: National Science Foundation, Documenting Endangered Languages program. The readme's for each work give further details. Additional works with new videos may be added in the future. See also the Deep Blue Data collections "Burkina Faso documentary videos" and "Central Mali documentary videos". The latter contains Mali videos archived in 2018.
- Keyword:
- Mali and documentary videos
- Discipline:
- Humanities
11Works -
- Creator:
- Ansong, Joseph K. and Arbic, Brian K.
- Description:
- This is the model and observational data referenced in our manuscript entitled “surface and sub-subsurface internal gravity wave kinetic energy spectra from global ocean models and observations.” The model data for the 7 regions from the two global simulations (HYCOM and MITgcm) can be found here.
- Keyword:
- vertical wavenumber spectra of internal waves, surface kinetic energy spectra, and ratio of high versus low-frequency surface kinetic energy
- Citation to related publication:
- Ansong, J.K., et al., "forthcoming", Surface and sub-subsurface internal gravity wave kinetic energy spectra in global ocean models and observations
- Discipline:
- Science
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- Creator:
- Brennan, Jonathan R
- Description:
- These files contain the raw data and processing parameters to go with the paper "Hierarchical structure guides rapid linguistic predictions during naturalistic listening" by Jonathan R. Brennan and John T. Hale. These files include the stimulus (wav files), raw data (BrainVision format), data processing parameters (matlab), and variables used to align the stimuli with the EEG data and for the statistical analyses reported in the paper (csv spreadsheet). and Updates in Version 2: - data in BrainVision format - added information about data analysis - corrected prePROCessing information for S02
- Keyword:
- Linguistics, Speech, and EEG
- Citation to related publication:
- Brennan, J. R., & Hale, J. T. (2019). Hierarchical structure guides rapid linguistic predictions during naturalistic listening. PLoS ONE 14(1). e0207741
- Discipline:
- Social Sciences
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- Creator:
- Cao, Yinyin, Lawson, Benn, and Pil, Frits K.
- Description:
- As part of a larger research study on social sustainability and human rights, this research examines the supplier codes of conduct lead firms adopt to achieve their social supply chain sustainability goals.
- Keyword:
- social sustainability, human rights, and supplier codes of conduct
- Citation to related publication:
- Cao, Y., Lawson, B., & Pil, F. K. (2023). Social sustainability and human rights in global supply chains, International Journal of Operations & Production Management, Vol. ahead-of-print No. ahead-of-print. https://doi.org/10.1108/IJOPM-10-2022-0670.
- Discipline:
- Business
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- Creator:
- Hoffmann, Alex P.
- Description:
- Research Overview: In situ magnetic field measurements are often difficult to obtain due to the presence of stray magnetic fields generated by spacecraft electrical subsystems. The conventional solution is to implement strict magnetic cleanliness requirements and place magnetometers on a deployable boom. However, this method is not always feasible on low-cost platforms due to factors such as increased design complexity, increased cost, and volume limitations. To overcome this problem, we propose using the Quad-Mag CubeSat magnetometer with an improved Underdetermined Blind Source Separation (UBSS) noise removal algorithm. The Quad-Mag consists of four magnetometer sensors in a single CubeSat form-factor card that allows distributed measurements of stray magnetic fields. The UBSS algorithm can remove stray magnetic fields without prior knowledge of the magnitude, orientation, or number of noise sources. UBSS is a two-stage algorithm that identifies signals through cluster analysis and separates them through compressive sensing. We use UBSS with single source point (SSP) detection to improve the identification of noise signals and iteratively-weighted compressed sensing to separate noise signals from the ambient magnetic field. Using a mock CubeSat, we demonstrate in the lab that UBSS reduces four noise signals producing more than 100 nT of noise at each magnetometer to below the expected instrument resolution (near 5 nT). Additionally, we show that the integrated Quad-Mag and improved UBSS system works well for 1U, 2U, 3U, and 6U CubeSats in simulation. Our results show that the Quad-Mag and UBSS noise cancellation package enables high-fidelity magnetic field measurements from a CubeSat without a boom.
- Keyword:
- source separation, demixing, magnetometers, stray magnetic fields, noise removal, and cubesat
- Citation to related publication:
- Hoffmann, A. P., Moldwin, M. B., Strabel, B. P., & Ojeda, L. V. (2023). Enabling Boomless CubeSat Magnetic Field Measurements with the Quad-Mag Magnetometer and an Improved Underdetermined Blind Source Separation Algorithm. Journal of Geophysical Research: Space Physics, 128, e2023JA031662. https://doi-org.proxy.lib.umich.edu/10.1029/2023JA031662
- Discipline:
- Engineering
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- Creator:
- McCuen, Brett A.
- Description:
- We present a comprehensive statistical analysis of high-frequency transient-large-amplitude (TLA) magnetic perturbation events that occurred at 12 high-latitude ground magnetometer stations throughout solar cycle 24 from 2009 to 2019. TLA signatures are defined as one or more second-timescale dB/dt interval with magnitude ≥ 6 nT/s within an hour event window. This study characterizes high-frequency TLA events based on their spatial and temporal behavior as well as relation to auroral substorms, geomagnetic storm phases and nighttime geomagnetic disturbance events events (GMD). We show that TLA events occur primarily at nighttime and solely in the high-latitude region above 60 degrees geomagnetic latitude. The largest TLA events occurred more often in the declining phase of the solar cycle when solar wind velocity was higher and ring current activity was lower, suggesting association to high-speed flows caused by coronal holes and subsequent corotating interaction regions reaching Earth. TLA perturbations often occurred preceding or within the most extreme nighttime geomagnetic disturbance (GMD) events with 5-10 minute timescales, but the TLA intervals were often even more localized than the ~300 km effective radius of GMDs: occurring at only some of the stations at which GMDs occurred. We show that TLA-related GMD events can result from dipolarization fronts in the magnetotail and fast flows toward Earth and are closely temporally associated to poleward boundary intensifications (PBI) and auroral streamers. The highly localized behavior and connection to the most extreme GMD events suggests that TLA intervals are a ground manifestation of the features within rapid and complex ionospheric structures that can drive GICs.
- Keyword:
- geomagnetic field, high frequency, space weather, transient-large-amplitude, TLA, high frequency dB/dt, dB/dt search algorithm
- Citation to related publication:
- McCuen, B. A., Moldwin, M. B., Engebretson, M. J., Weygand, J. G., Nishimura, Y. (2023). A Statistical Analysis of High-frequency Transient-Large-Amplitude Geomagnetic Disturbance. [To be submitted to] Journal of Geophysical Research: Space Physics
- Discipline:
- Science
-
- Creator:
- Brennan, Jonathan R.
- Description:
- These files contain the raw data and processing parameters to go with the paper "Hierarchical structure guides rapid linguistic predictions during naturalistic listening" by Jonathan R. Brennan and John T. Hale. These files include the stimulus (wav files), raw data (matlab format for the Fieldtrip toolbox), data processing paramters (matlab), and variables used to align the stimuli with the EEG data and for the statistical analyses reported in the paper.
- Keyword:
- linguistics, syntax, language, and eeg
- Citation to related publication:
- Brennan JR, Hale JT (2019) Hierarchical structure guides rapid linguistic predictions during naturalistic listening. PLoS ONE 14(1): e0207741. https://doi.org/10.1371/journal.pone.0207741
- Discipline:
- Social Sciences
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Bozo languages of Mali (spreadsheets, media)
User Collection- Creator:
- Heath, Jeffrey G.
- Description:
- This collection will archive lexical spreadsheets, audio files, geographic information, images, and videos that complement the reference grammars in pdf and docx form in the collection “Bozo languages of Mali (documents)” that are archived in Deep Blue Documents ( https://dx.doi.org/10.7302/6632). See the “readme” for that collection and the introductory material in the reference grammars for general information about the languages and the fieldwork., The initial material archived in the present collection consists of audio files. They are recordings of narratives, interviews, and conversations. Some of them have been transcribed and are presented as appendices in the reference grammars. Others have not been transcribed; they are presented here in the hope that they can eventually be transcribed or at least listened to by native speakers. If the author is able to transcribe some of them in the future, the transcriptions will be added here (and to the Deep Blue Documents collection)., Many of the recordings, as well as most of the images and videos to be added to this collection, have been made by project assistant Minkailou Djiguiba. He has courageously traveled into Bozo-speaking zones, some of which are highly insecure, to do this work. In addition, he has been instrumental in recruiting and transporting Bozo speakers to the author’s base in Bobo Dioulasso where much of the grammatical and lexical work has been done., and The author’s fieldwork is supported by grant PD-1941828 (2020-2024) from the National Science Foundation, Documenting Endangered Languages program, which is also supported by the National Endowment for the Humanities.
- Keyword:
- Bozo, Jenaama, Cliffs, Kelenga, Tigemaxo, and Tiéyaxo
- Discipline:
- Humanities
8Works