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- Creator:
- Ozturk, Dogacan Su
- Description:
- The rapid increases in solar wind dynamic pressure, termed sudden impulses (SIs), compress Earth’s dayside magnetosphere and strongly perturb the coupled Magnetosphere-Ionosphere (M-I) system. The compression of the dayside magnetosphere launches magnetohydrodynamic (MHD) waves, which propagate down to the ionosphere, changing the Auroral Field Aligned Currents (FACs), and into nightside magnetosphere. The global response to the compression front sweeping through the coupled system is not yet fully understood due to the sparseness of the measurements, especially those with the necessary time resolution to resolve the propagating disturbances. That’s why a study including modeling is necessary. On 15 August 2015 at 7.44 UT, Advanced Composition Explorer measured a sudden increase in the solar wind dynamic pressure from 1.11 nPa to 2.55 nPa as shown in Figure-1. We use the magnetospheric spacecraft in the equatorial magnetosphere to identify the signatures of magnetosphere response to this SI event and examine the interaction of the propagating disturbances with the M-I system. With the increased time resolution of Active Magnetosphere and Polar Electrodynamics Response Experiment (AMPERE), the FAC pattern and intensity change due to SI can also be studied in more depth. We further use measurements from ground based magnetometer stations to increase our tracking capability for the disturbances in the ionosphere and to improve our understanding of their propagation characteristics. This is the first step in a comprehensive multi-point observation and a global magnetohydrodynamic simulation based investigation of the response of the coupled M-I system to sudden impulses.
- Citation to related publication:
- Ozturk, Doga & Zou, Shasha & Slavin, James. (2016). The Response of the Coupled Magnetosphere-Ionosphere System to the 15 August 2015 Solar Wind Dynamic Pressure Enhancement. https://www.researchgate.net/publication/300020219
- Discipline:
- Science
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- Creator:
- Hille, Madeline M., Clark, Marin K., Gronewold, Andrew D., West, A. Joshua, Zekkos, Dimitrios , and Chamlagain, Deepak
- Description:
- This dataset supports the findings of Hille et al. (2021, in review) in Geophysical Research Letters. In this article, we present a multivariate analysis of extreme storm events that occur during the Indian summer monsoon over the Himalayan Range in central Nepal. We resolve storm events at sub daily durations by merging NASA’s Global Precipitation Mission (GPM) Integrated Multi-satellitE Retrievals for GPM (IMERG) 30-minute, gridded 0.1x0.1-degree precipitation product with local rain gauges operated by the Nepal Department of Hydrology and Meteorology (DHM) and the International Centre for Integrated Mountain Development (ICIMOD). We quantify spatial variability in extreme rainfall by isolating storms over a specific intensity threshold and pairing a principal components analysis with a K-means clustering approach to group storms of similar characteristics. and We find that frequent and intense storms occur over the forefront of the central Himalayan range and coincide with a locus of monsoon-driven landslide density. This pattern agrees with observations of elevated annual precipitation volumes near the Himalayan physiographic transition from low to high relief (Bookhagen and Burbank, 2010), and is consistent with orographically-influenced rainfall over other mountain ranges (Marra et al., 2021). In addition to presenting novel methodology to quantifying storm variability, our results highlight the strong orographic effect on precipitation intensity and duration, as well as an association of shallow bedrock landsliding frequency with intense precipitation.
- Keyword:
- orographic rainfall, multivariate analysis, extreme rainfall events, and rainfall-triggered landslides
- Citation to related publication:
- Hille et al. (2021, in review). The orographic influence on storm variability, extreme rainfall characteristics and rainfall-triggered landsliding. Geophysical Research Letters. Forthcoming
- Discipline:
- Science
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- Creator:
- Cheng, Hao Fei, Hecht, Brent , Wheeler, Earnest, Wang, Xinyi, Zhu, Haiyi, and Dillahunt, Tawanna R
- Description:
- The sharing economy has quickly become a very prominent subject of research in the broader computing literature and the in human–computer interaction (HCI) literature more specifically. When other computing research areas have experienced similarly rapid growth (e.g. human computation, eco-feedback technology), early stage literature reviews have proved useful and influential by identifying trends and gaps in the literature of interest and by providing key directions for short- and long-term future work. In this paper, we seek to provide the same benefits with respect to computing research on the sharing economy. Specifically, following the suggested approach of prior computing literature reviews, we conducted a systematic review of sharing economy articles published in the Association for Computing Machinery Digital Library to investigate the state of sharing economy research in computing. We performed this review with two simultaneous foci: a broad focus toward the computing literature more generally and a narrow focus specifically on HCI literature. We collected a total of 112 sharing economy articles published between 2008 and 2017 and through our analysis of these papers, we make two core contributions: (1) an understanding of the computing community’s contributions to our knowledge about the sharing economy, and specifically the role of the HCI community in these contributions (i.e. what has been done) and (2) a discussion of under-explored and unexplored aspects of the sharing economy that can serve as a partial research agenda moving forward (i.e. what is next to do).
- Keyword:
- Collaborative and social computing, Human-computer interaction interaction, and Human-centered computing
- Citation to related publication:
- Dillahunt, T. R., Wang, X., Wheeler, E., Cheng, H. F., Hecht, B., & Zhu, H. (2017). The Sharing Economy in Computing: A Systematic Literature Review. Proceedings of the ACM on Human-Computer Interaction, 1(CSCW), 38:1-38:26. https://doi.org/10.1145/3134673
- Discipline:
- Other
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- Creator:
- Bueno-Junior, Lezio S., Ruckstuhl, Maxwell S., Lim, Miranda M., and Watson, Brendon O.
- Description:
- Rapid eye movement sleep (REM) is believed to have a binary temporal structure with “phasic” and “tonic" microstates, characterized by motoric activity versus quiescence, respectively. However, we observed in mice that the frequency of theta activity (a marker of rodent REM) fluctuates in a non-binary fashion, with the extremes of that fluctuation correlating with phasic-type and tonic-type facial motricity. Thus, phasic and tonic REM may instead represent ends of a continuum. These cycles of brain physiology and facial movement occurred at 0.01-0.06 Hz, or infraslow frequencies, and affected cross-frequency coupling and neuronal activity in the neocortex, suggesting network functional impact. We then analyzed human data and observed that humans also demonstrate non-binary phasic/tonic microstates, with continuous 0.01-0.04 Hz respiratory rate cycles matching the incidence of eye movements. These fundamental properties of REM can yield new insights into our understanding of sleep health.
- Keyword:
- REM sleep, Infraslow fluctuations, Facial movements, Theta oscillations, and Respiration rate
- Citation to related publication:
- L. S. Bueno-Junior, M. S. Ruckstuhl, M. M. Lim, B. O. Watson, The temporal structure of REM sleep shows minute-scale fluctuations across brain and body in mice and humans. Proc. Natl. Acad. Sci. U. S. A. In press (2023).
- Discipline:
- Science
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- 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
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- Creator:
- Ponder, Brandon M., Ridley, Aaron J., Bougher, Stephen W., Pawlowski, David, and Brecht, Amanda
- Description:
- This research was completed to introduce a state-of-the-art Venus GCM to the modeling community. Validation studies were performed to give credence to the model's results. and This data set is made available under a Creative Commons Public Domain license (CC0 1.0). The python scripts contained were ran on macOS Monterey version 12.7 with Python 3.9. Numpy version: 1.19.4 Pandas version: 1.2.0
- Keyword:
- Venus, GITM, Ionosphere, Thermosphere, Solar minimum, Navier-stokes, Fluid dynamics, Shocks, V-GITM, and VGITM
- Citation to related publication:
- Ponder, Brandon & Ridley, Aaron J. & Bougher, Stephen W. & Pawlowski, D. & Brecht, A. (2023). The Venus Global Ionosphere-Thermosphere Model (V-GITM): A Coupled Thermosphere and Ionosphere Formulation. JGR Planets. In Press.
- Discipline:
- Science
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- 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
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- Creator:
- Heath, Jeffrey
- Description:
- Images of villages in Mali in which Tiranige (Dogon family) is the primary language. Each file name contains important information about the photos, and are structured thus: LanguageFamily_Language_IdentificationNumber_GeographicCoordinate_Description_Date_InitialsOfThePhotographer
- Keyword:
- villages, Dogon, Tiranige, and Mali
- Citation to related publication:
- Moran, Steven & Forkel, Robert & Heath, Jeffrey (eds.) 2016. Dogon and Bangime Linguistics. Jena: Max Planck Institute for the Science of Human History. http://dogonlanguages.org
- Discipline:
- Humanities
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- Creator:
- Heath, Jeffrey
- Description:
- Images of villages in Mali in which Tommo So (Dogon family) is the primary language. Each file name contains important information about the photos, and are structured thus: LanguageFamily_Language_IdentificationNumber_GeographicCoordinate_Description_Date_InitialsOfThePhotographer
- Keyword:
- villages, Dogon, Tommo So, and Mali
- Citation to related publication:
- Moran, Steven & Forkel, Robert & Heath, Jeffrey (eds.) 2016. Dogon and Bangime Linguistics. Jena: Max Planck Institute for the Science of Human History. http://dogonlanguages.org
- Discipline:
- Humanities
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- Creator:
- Heath, Jeffrey
- Description:
- Images of villages in Mali in which Tomo Kan(Dogon family) is the primary language. Each file name contains important information about the photos, and are structured thus: LanguageFamily_Language_IdentificationNumber_GeographicCoordinate_Description_Date_InitialsOfThePhotographer
- Keyword:
- villages, Dogon, Tomo Kan, and Mali
- Citation to related publication:
- Moran, Steven & Forkel, Robert & Heath, Jeffrey (eds.) 2016. Dogon and Bangime Linguistics. Jena: Max Planck Institute for the Science of Human History. http://dogonlanguages.org
- Discipline:
- Humanities