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- Creator:
- Adam Schneider and Mark Flanner
- Description:
- This dataset contains all data used to generate the figures in The Cryosphere manuscript “Measuring Snow Specific Surface Area with 1.30 and 1.55 micro-meter Bidirectional Reflectance Factors,” by Adam Schneider, Mark Flanner, and Roger De Roo. These data support the theory, calibration, and application of the Near-Infrared Emitting and Reflectance Monitoring Dome (NERD), an instrument engineered to rapidly retrieve surface snow specific surface area in the field. Note that this deposit includes a microCT scan database for natural snowfall samples collected in New Hampshire during 2015-2017, comprised of raw tiff files as well as reconstructions, binarized reconstructions, and some 3D model reconstructions. and Running python scripts generally require that the following packages are installed: NumPy, SciPy, Matplotlib, Pandas, and ipdb (for debugging).
- Keyword:
- Snow specific surface area, Monte Carlo, X-ray micro-computed tomography, SNICAR, Near-Infrared Emitting and Reflectance-Monitoring Dome, Bidirectional reflectance factor, Cryosphere, and 3D
- Discipline:
- Science
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- Creator:
- Huang, Yihe
- Description:
- Geological and geophysical observations reveal along-strike fault zone heterogeneity on major strike-slip faults, which can play a significant role in earthquake rupture propagation and termination. I present 2D dynamic rupture simulations to demonstrate rupture characteristics in such heterogeneous fault zone structure. The modeled rupture is nucleated in a damaged fault zone and propagates on a preexisting fault towards the zone of intact rocks. There is an intermediate range of nucleation lengths that only allow rupture to spontaneously propagate in the damaged fault zone but not in a homogeneous medium. I find that rupture with an intermediate nucleation length tends to stop when it reaches the zone of intact rocks, especially when the rupture propagation distance in the damaged fault zone is relatively short and when the damaged fault zone is relatively narrow or smooth in the fault-normal direction. Pronounced small-scale heterogeneity within the damaged fault zone also contributes to such early rupture termination. In asymmetric fault zones bisected by a bimaterial fault, rupture moving in the direction of slip of faster rocks tends to terminate under the same conditions as in symmetric fault zones, whereas rupture moving in the direction of slip of slower rocks can penetrate into the zone of intact rocks. Break-through rupture is allowed when a sufficiently-large asperity is located at the edge of the zone of intact rocks. The results suggest the along-strike fault zone heterogeneity can play a critical role in seismicity distribution. The data set contains multiple folders of simulation results from the SEM2DPACK that demonstrate the above findings. The folder name includes the model parameters in each simulation as explained in the README file. The Flt01_sem2d.data file in the folder documents the slip, slip rate and stresses from each simulation. The files are also explained in the manual of SEM2DPACK ( http://web.gps.caltech.edu/~ampuero/soft/users_guide_sem2dpack.pdf). Please refer to section 4.6 in the manual and use “sem2d_read_fault.m” in the POST folder of SEM2DPACK to plot the results.
- Keyword:
- Damaged fault zone, fault zone heterogeneity, earthquake rupture termination, and seismicity distribution
- Discipline:
- Science
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- Creator:
- Penner, Joyce E., Zhou, Cheng, Garnier, Anne, and Mitchell, David
- Description:
- This data set contains the scripts and data sets needed to create the 9 figures in the referenced publication.
- Keyword:
- Anthropogenic Aerosol indirect effects, cirrus clouds, and ice nucleation
- Citation to related publication:
- Penner, J. E., Zhou, C., Garnier, A., & Mitchell, D. L. (2018). Anthropogenic aerosol indirect effects in cirrus clouds. Journal of Geophysical Research: Atmospheres,123, 11,652–11,677. https://doi.org/10.1029/2018JD029204
- Discipline:
- Science
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- Creator:
- Mirshams Shahshahani, Payam
- Description:
- Investigating minimum human reaction times is often confounded by the motivation, training, and state of arousal of the subjects. We used the reaction times of athletes competing in the shorter sprint events in the Athletics competitions in recent Olympics (2004-2016) to determine minimum human reaction times because there's little question as to their motivation, training, or state of arousal. The reaction times of sprinters however are only available on the IAAF web page for each individual heat, in each event, at each Olympic. Therefore we compiled all these data into two separate excel sheets which can be used for further analyses.
- Keyword:
- minimum reaction time, sprinter, Olympics, Athletics, sex difference, starting block, and false start
- Citation to related publication:
- Mirshams Shahshahani P, Lipps DB, Galecki AT, Ashton-Miller JA (2018) On the apparent decrease in Olympic sprinter reaction times. PLoS ONE 13(6): e0198633. https://doi.org/10.1371/journal.pone.0198633
- Discipline:
- Engineering, Health Sciences, Science, Other, and General Information Sources
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- Creator:
- Nguyen, Thanh H., Wright, Mason, Wellman, Michael P., and Singh, Satinder
- Description:
- In this work , we study the problem of allocating limited security countermeasures to protect network data from cyber-attacks, for scenarios modeled by Bayesian attack graphs. We consider multi-stage interactions between a network administrator and cybercriminals, formulated as a security game. We propose parameterized heuristic strategies for the attacker and defender and provide detailed analysis of their time complexity. Our heuristics exploit the topological structure of attack graphs and employ sampling methods to overcome the computational complexity in predicting opponent actions. Due to the complexity of the game, we employ a simulation-based approach and perform empirical game analysis over an enumerated set of heuristic strategies. Finally, we conduct experiments in various game settings to evaluate the performance of our heuristics in defending networks, in a manner that is robust to uncertainty about the security environment.
- Keyword:
- Empirical Game-Theoretic Analysis, Multi-stage Security Games, Attack Graph, Game Theory, and Moving Target Defense
- Discipline:
- Science and Engineering
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- Creator:
- Bemmels, Jordan B. and Dick, Christopher W.
- Description:
- Raw SNP genotypes are provided in STRUCTURE format, with a maximum of one SNP reported per ddRAD locus. The files "caryco_SNP.str" and "caryov_SNP.str" are genotypes for Carya cordiformis and Carya ovata, respectively. The first column of each file is the individual name, the second column is the population (see original publication for information on population locations), and the remaining columns are genotypes of individual SNPs. Rows represent individuals, with the diploid genotypes contained on two lines per individual. Missing data are entered as "0" (zero). The first row is a header with a unique identifier for each SNP. and Occurrence records for each species are provided in the file "occs_carya.csv" and contain the latitude and longitude of each record.
- Keyword:
- eastern North America, glacial refugia, phylogeography, temperate trees, and single nucleotide polymorphisms
- Citation to related publication:
- Bemmels, J.B., and C.W. Dick. 2018. Genomic evidence of a widespread southern distribution during the Last Glacial Maximum for two North American hickory species. Journal of Biogeography, 45: 1739– 1750. https://doi.org/10.1111/jbi.13358
- Discipline:
- Science
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- Creator:
- Welling, Daniel and Walsh, Brian
- Description:
- The goal of this simulation was to examine the spread of magnetic reconnection across the dayside magnetopause upon the arrival of a tangential discontinuity of the interplanetary magnetic field from a purely northward to southward configuration. Simple solar wind conditions were used to give us input into the system. A very high resolution grid setup was used in BATS-R-US.
- Keyword:
- space science, magnetosphere, magnetohydrodynamics, magnetopause, and magnetic reconnection
- Citation to related publication:
- Walsh, B. M., Welling, D. T.,Zou, Y., & Nishimura, Y. (2018). A maximum spreading speed for magnetopause reconnection. Geophysical Research Letters, 45, 5268–5273. https://doi.org/10.1029/2018GL078230
- Discipline:
- Science
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- Creator:
- Ward, Jamie L ., Flanner, Mark G., Bergin, Mike, Dibb, Jack E., Polashenski, Chris M., Soja, Amber J., and Thomas, Jennie L.
- Description:
- Biomass burning produces smoke aerosols that are emitted into the atmosphere. Some smoke constituents, notably black carbon (BC), are highly effective light-absorbing aerosols (LAA). Emitted LAA can be transported to high albedo regions like the Greenland Ice Sheet (GrIS) and affect local snowmelt. In the summer, the effects of LAA in Greenland are uncertain. To explore how LAA affect GrIS snowmelt and surface energy flux in the summer, we conduct idealized global climate model simulations with perturbed aerosol amounts and properties in the GrIS snow and overlying atmosphere. The in-snow and atmospheric aerosol burdens we select range from background values measured on the GrIS to unrealistically high values. This helps us explore the linearity of snowmelt response and to achieve high signal-to-noise ratios. With LAA operating only in the atmosphere, we find no significant change in snowmelt due to the competing effects of surface dimming and tropospheric warming. Regardless of atmospheric LAA presence, in-snow BC-equivalent mixing ratios greater than ~60 ng/g produce statistically significant snowmelt increases over much of the GrIS. We find that net surface energy flux changes correspond well to snowmelt changes for all cases. The dominant component of surface energy flux change is solar energy flux, but sensible and longwave energy fluxes respond to temperature changes. Atmospheric LAA dampen the magnitude of solar radiation absorbed by in-snow LAA when both varieties are simulated. In general, the significant melt and surface energy flux changes we simulate occur with LAA quantities that have never been recorded in Greenland.
- Keyword:
- climate, Greenland Ice Sheet, black carbon, biomass burning, snowmelt, and surface energy balance
- Citation to related publication:
- Ward, J.L., et al. (2018). Modeled Response of Greenland Snowmelt to the Presence of Biomass Burning-Based Absorbing Aerosols in the Atmosphere and Snow. Journal of Geophysical Research: Atmospheres. 123, 6122– 6141. https://doi.org/10.1029/2017JD027878
- Discipline:
- Science
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- Creator:
- Wozniak, Matthew C., Steiner, Allison L., and Solmon, Fabien
- Description:
- Pollen grains emitted from vegetation can rupture, releasing subpollen particles (SPPs) as fine atmospheric particulates. Previous laboratory research demonstrates potential for SPPs as efficient cloud condensation nuclei (CCN). We develop the first model of atmospheric pollen grain rupture, and implement the mechanism in regional climate model simulations over spring pollen season in the United States with a CCN-dependent moisture scheme. The source of SPPs (surface or in-atmosphere) depends on region and sometimes season, due to the distribution of relative humidity and rain. Simulated concentrations of SPPs are approximately 1-10 or 1-1,000 cm-3, depending on the number of SPPs produced per pollen grain (nspg). Lower nspg (103) produces a negligible effect on precipitation, but high nspg (106) in clean continental CCN background concentrations (100 CCN cm-3) shows SPPs suppress average seasonal precipitation by 32% and shift rates from heavy to light while increasing dry days. This effect is likely smaller for polluted air. pollen_rupture_precipitation_BASE_ensemble_daily.nc - data for BASE ensemble average pollen_rupture_precipitation_SPPHIGH_ensemble_daily.nc - data for SPPHIGH ensemble average pollen_rupture_precipitation_SPPLIT_ensemble_daily.nc - data for SPPLIT ensemble average
- Discipline:
- Science
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- 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