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- Creator:
- dos Santos, Thiago, Steiner, Allison, Keppel-Aleks, Gretchen, and De Roo, Roger
- Description:
- Model simulations were conducted to investigate the role of soil moisture on the terrestrial carbon and water cycles. The data are composed of NetCDF files generated by the simulations that contain the data variables analyzed in the paper. and CLM5 Documentation - http://www.cesm.ucar.edu/models/cesm2/land/.
- Keyword:
- Soil moisture, Community Land Model 5, Latent heat, GPP, Gross primary productivity, and Fluxnet
- Citation to related publication:
- Santos, T. dos, Keppel-Aleks, G., Roo, R. D., & Steiner, A. L. (2021). Can Land Surface Models Capture the Observed Soil Moisture Control of Water and Carbon Fluxes in Temperate-To-Boreal Forests? Journal of Geophysical Research: Biogeosciences, 126(4), e2020JG005999. https://doi.org/10.1029/2020JG005999
- Discipline:
- Science
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- Creator:
- Ruas, Terry, Ferreira, Charles H. P., Grosky, William, França, Fabrício O., and Medeiros, Débora M. R,
- Description:
- The relationship between words in a sentence often tell us more about the underlying semantic content of a document than its actual words, individually. Recent publications in the natural language processing arena, more specifically using word embeddings, try to incorporate semantic aspects into their word vector representation by considering the context of words and how they are distributed in a document collection. In this work, we propose two novel algorithms, called Flexible Lexical Chain II and Fixed Lexical Chain II that combine the semantic relations derived from lexical chains, prior knowledge from lexical databases, and the robustness of the distributional hypothesis in word embeddings into a single decoupled system. In short, our approach has three main contributions: (i) unsupervised techniques that fully integrate word embeddings and lexical chains; (ii) a more solid semantic representation that considers the latent relation between words in a document; and (iii) lightweight word embeddings models that can be extended to any natural language task. Knowledge-based systems that use natural language text can benefit from our approach to mitigate ambiguous semantic representations provided by traditional statistical approaches. The proposed techniques are tested against seven word embeddings algorithms using five different machine learning classifiers over six scenarios in the document classification task. Our results show that the integration between lexical chains and word embeddings representations sustain state-of-the-art results, even against more complex systems. Github: https://github.com/truas/LexicalChain_Builder
- Keyword:
- document classification, lexical chains, word embeddings, synset embeddings, chain2vec, and natural language processing
- Citation to related publication:
- Terry Ruas, Charles Henrique Porto Ferreira, William Grosky, Fabrício Olivetti de França, Débora Maria Rossi de Medeiros, "Enhanced word embeddings using multi-semantic representation through lexical chains", Information Sciences, 2020, https://doi.org/10.1016/j.ins.2020.04.048
- Discipline:
- Other, Science, and Engineering
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- Creator:
- Trung, Huy-Sinh, Liemohn, Michael W, and Ilie, Raluca
- Description:
- The goal of this research was to understand structures where the solar wind plasma contribution to the total plasma was equal to the ionospheric plasma. This simulation was performed over a simulation time of 12 hours for 4 different plasma compositions for 2 different solar wind profiles., The SWMF used the Block Adaptive Tree Solar wind Roe-type Upwind Scheme version 9.20. It can be found at http://csem.engin.umich.edu/tools/swmf/downloads.php. These data can be processed using the simulation code deposited at the Deep Blue Data record indicated in the "Citation to related material" field., and To cite this data set: Trung, H.-S., Liemohn, M., W., Ilie, R. (2019). 12 hour data for magnetospheric simulations for a multifluid plasma for 8 different configurations [Data set]. University of Michigan Deep Blue Data Repository. https://doi.org/10.7302/fwq2-ey41
- Keyword:
- Space Physics, Magnetospheres, and 3D
- Citation to related publication:
- Trung, H.-S., Liemohn, M.W. Ilie, R. (2019). Steady State Characteristics of the Terrestrial Geopause [Data set]. University of Michigan Deep Blue Data Repository. https://doi.org/10.7302/7w13-kq27
- Discipline:
- Science
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- Creator:
- Li, Yang and Steiner, Allison
- Description:
- WRF-Chem simulation with 1.33 km resolution using the MYJ PBL scheme over the Baltimore-Washington region and WRF-Chem simulation with 1.33 km resolution using the YSU PBL scheme over the Baltimore-Washington region
- Keyword:
- LES, WRF-Chem, vertical mixing, oxidants, boundary layer dynamics
- Citation to related publication:
- Li, Y., Barth, M. C., and Steiner, A. L.: Comparing turbulent mixing of atmospheric oxidants across model scales, Atmospheric Environment, 199, 88-101, https://doi.org/10.1016/j.atmosenv.2018.11.004, 2018.
- Discipline:
- Science
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- Creator:
- Morales, Annareli
- Description:
- The research that produced this data involves exploring the sensitivity of orographic precipitation to changes in microphysical parameters found in the Morrison microphysics scheme within CM1 model. These microphysical sensitivities are also tested within different environments. The tests can be described as "one-at-a-time" experiments, i.e., an individual parameter is perturbed while keeping the rest constant. Annareli Morales conducted this research for her PhD research while working at the Mesoscale and Microscale Meteorology lab at NCAR in Boulder, CO.
- Keyword:
- Orographic precipitation
- Citation to related publication:
- Morales, A., H. Morrison, and D. Posselt, 2018: Orographic precipitation response to microphysical parameter perturbations for idealized moist nearly neutral flow. Journal of Atmospheric Science, 75, 1933-1953, https://doi.org/10.1175/JAS-D-17-0389.1
- Discipline:
- Science
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- Creator:
- Burleigh, M.
- Description:
- Brightness from an all-sky imager has been used as a spatiotemporal constraint for auroral inputs selected from in situ rocket measurements which are used to drive the ionospheric model. This method allows for realistic ionospheric forcing that is not captured in traditional "on-off" methods of describing PMAFs. Transient forcing (simulated PMAFs) and steady forcing ("on-off") simulations have been generated for comparison.
- Keyword:
- Poleward moving auroral forms, High-latitude ionosphere, Ionospheric modeling, Transient forcing, PMAF, GEMINI-TIA, and RENU2
- Citation to related publication:
- Burleigh, M., Zettergren, M., Lynch, K., Lessard, M., Moen, J., Clausen, L., Kenward, D., Hysell, D., and Liemohn, M. (2019). Transient ionospheric upflow driven by poleward moving auroral forms observed during the Rocket Experiment for Neutral Upwelling 2 (RENU2) campaign. Geophysical Research Letters. (Submitted).
- Discipline:
- Science
-
Galaxy Shape Catalogs for Dark Energy Survey Science Verification (DES-SV) Data - Additional Regions
- Creator:
- Das, Rutuparna and Dark Energy Survey (DES)
- Description:
- This dataset is associated with the University of Michigan Dept. of Physics dissertation titled "Shedding Light on the Dark: Exploring the Relation Between Galaxy Cluster Mass and Temperature Through Weak Gravitational Lensing" by Rutuparna Das. It is also associated with a paper, currently in preparation, by Das et al (details to be added once paper is submitted/accepted)., This work contains information about shapes of galaxies observed by the Dark Energy Survey (DES) during its Science Verification (SV) run. The official DES SV shape catalog has already been released to the public (see details in Jarvis et al. (2016), henceforth called "J16"). This work follows the methods presented in J16, and contains shapes from areas of the sky that were not processed as part of the official DES-SV catalog but were necessary for the work presented in the aforementioned dissertation. Each catalog contains information for galaxies in a 80′ × 80′ cutout centered at a given galaxy cluster., Note that these catalogs are not entirely analogous to the official DES-SV catalog. For one, we only measure shapes for galaxies, as stars and other objects were not needed for the dissertation. Our catalogs also only extend to a magnitude of 24 in r-band, whereas a small fraction of the objects in the official Im3shape catalog are dimmer (see Figure 29 of J16)., We also include other information necessary for weak lensing studies. Aside from all fields from Im3shape and noise bias calibration (listed and described in J16), these catalogs contain columns for object positions (“ra_gold”, “dec_gold”) and magnitudes in various filters (“mag_detmodel_g”, “mag_detmodel_r”, “mag_detmodel_i”, “mag_detmodel_z”) from the SVA1-Gold catalog ( https://des.ncsa.illinois.edu/releases/sva1/docs/docs-gold). Additionally, we include mean redshift measurements from two DES photo-z measurement pipelines, TPZ and DESDM Neural Network (“z_TPZ”, “z_DESDMnn”) (more details in Sanchez et al. (2014))., and References: Jarvis, M., Sheldon, E., Zuntz, J., et al. 2016, Monthly Notices of the Royal Astronomical Society, 460, 2245. Sanchez, C., Carrasco Kind, M., Lin, H., et al. 2014, Monthly Notices of the Royal Astronomical Society, 445, 1482.
- Keyword:
- weak lensing, galaxy clusters, galaxy shapes, cluster cosmology, Dark Energy Survey, DES, and galaxy shape catalogs
- Discipline:
- Science
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- Creator:
- A. Abeid, Bachir , L. Fabiilli, Mario , Aliabouzar, Mitra, and Estrada, Jon B.
- Description:
- Images of droplet dynamics during and after optical excitation experiments were recorded in the ultra-fast regime at 1 million frames per second (fps) while the low-speed, quasi-static evolution was carried at 1 fps. During both the inertial and quasi-static phases, we record 1–3 frames in the reference configuration prior to the arrival of the laser-pulse to distinguish the bubble from the background. Lastly, due to the complex physics of plasma formation and chemistry, forward simulations begin at the time when the bubble reaches its maximum expansion
- Keyword:
- optical droplet vaporization, cavitation, viscoelasticity, ultra-high-speed imaging, hydrogel, numerical modeling.
- Citation to related publication:
- Abeid, Bachir A, et al. (2024). Experimental and numerical investigations of ultra-high-speed dynamics of optically induced droplet cavitation in soft materials
- Discipline:
- Science and Engineering
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- Creator:
- Ye, Zhengwei and Mi, Zetian
- Description:
- Generation of C2+ compounds using sunlight, carbon dioxide, and water provides a promising path for carbon neutrality. The exploration of a catalyst to break the bottleneck of C-C coupling, for constructing a rational artificial photosynthesis integrated device, is at the core. Herein, based on operando spectroscopy measurements, theoretical calculations, and feedstock experiments, it is discovered that gold, in conjunction with iridium, can catalyze the reduction of CO2, achieving C-C coupling by insertion of CO2 into -CH3. Owing to a combination of optoelectronic and catalytic properties, the assembly of AuIr with InGaN nanowires on silicon (AuIr@InGaN NWs/Si) enables the achievement of a C2H6 activity of 58.8 mmol‧g-1‧h-1 with a turnover number of 54,595 over 60 hours. A light-to-fuels efficiency of ~0.59% for solar fuels production from CO2 and H2O is achieved without any other energy inputs. This work provides a carbon-negative path for producing higher order C compounds.
- Keyword:
- Carbon dioxide reduction and Photocatalysis
- Discipline:
- Science
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- Creator:
- Quartey, Nii-Boi A and Liemohn, Michael W
- Description:
- This dataset contains results from the BATS-R-US multispecies MHD code simulating the solar wind interaction at Mars at the following orbital and solar cycle locations: solar maximum at perihelion, solar maximum at aphelion, solar minimum at perihelion, solar minimum at aphelion. These simulations contain results with and without the crustal magnetic fields and includes variables such as the magnetic field and ion density.
- Keyword:
- mars, magnetosphere, magnetotail, current sheet, asymmetry, multispecies, multifluid, MHD, and MAVEN
- Discipline:
- Science