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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Generalized Contingency Analysis Based on Graph Theory and Line Outage Distribution Factor
Not provided.
Using Reinforcement Learning to Increase Grid Security Under Contingency Conditions.
Abstract not provided.
A Configurable Hierarchical Architecture for Parallel Dynamic Contingency Analysis on GPUs
Not Available
A Visualization Tool for Real-Time Dynamic Contingency Screening and Remedial Actions
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Modified niche optima and breadths explain the historical contingency of bacterial community responses to eutrophication in coastal sediments
Abstract Previous studies have shown that the response of bacterial communities to disturbances depends on their environmental history. Historically fluctuating habitats host communities that respond better to disturbance than communities of historically stable habitats. However, the exact ecological mechanism that drives this dependency remains unknown. Here, we experimentally demonstrate that modifications of niche optima and niche breadths of the community members are driving this dependency of bacterial responses to past environmental conditions. First, we develop a novel, simple method to calculate the niche optima and breadths of bacterial taxa regarding single environmental gradients. Then, we test this method on sediment bacterial communities of three habitats, one historically stable and less loaded and two historically more variable and more loaded habitats in terms of historical chlorophyll‐α water concentration, that we subject to hypoxia via organic matter addition ex situ . We find that communities containing bacterial taxa differently adapted to hypoxia show different structural and functional responses, depending on the sediment's environmental history. Specifically, in the historically less fluctuating and loaded sediments where we find more taxa poorly adapted to hypoxic conditions, communities change a lot over time and organic matter is not degraded efficiently. The opposite is true for the historically more fluctuating and loaded sediments where we find more taxa well adapted to hypoxia. Based on the community responses observed here, we also propose an alternative calculation of community resistance that takes into account how rapidly the communities respond to disturbances and not just the initial and final states of the community.
Relaxations of AC Minimal Load-Shedding for Severe Contingency Analysis
No abstract provided.
Parallel Computing for Massive Dynamic Contingency Analysis
The first step towards running PSLF in a high-performance computing (HPC) environment was porting PSLF to the Linux operating system from the current shipping target of MS Windows. The target machine was the LLNL Quartz system which is a Linux cluster configured for large parallel jobs. It has 2,688 batch nodes with Dual Socket Intel E5-2695 v4 (Broadwell) CPUs with 18 cores each, with a total of 344,064 GB of memory, each node having 128 GB of memory. Nodes are connected with an Intel Omni-Path 100 GB/s interconnect. Quartz runs the Tri-Laboratory Operating System Software (TOSS) that includes Red Hat Enterprise Linux (RHEL) distribution used on the LLNL HPC machines.
Deployable Wind Turbines to Enhance Contingency Base Resilience.
Abstract not provided.
Using Reinforcement Learning to Increase Grid Security Under Contingency Conditions.
Abstract not provided.
Using Reinforcement Learning to Increase Grid Security under Contingency Conditions.
Abstract not provided.
Therapeutic efficacy of a potent anti-VEEV antibody is contingent on humoral and cell-mediated cytotoxic immunity.
Abstract not provided.
Ripple-Type Voltage Control for Extreme-Event Contingencies: Preprint
Frequent and intense extreme events make grid operation unprecedentedly challenging. Disruptive events could lead to dangerous voltage drops and even voltage collapse if corrective actions are not quickly taken. In this paper, we present a real-time algorithm for voltage control suitable for mitigating electric grid damage scenarios. In our strategy, when agents (generators, substations) experience a dangerous undervoltage, they first respond locally. When the local control resources are depleted, agents seek assistance from peer nodes over a communication network. The algorithm is simulated on a realistic test transmission system. Using fragility curve methodology, we simulate hurricane damages to the components of the synthetic 2000-bus grid representing the ERCOT system. Although being tested over a damaged grid after a hurricane event, our algorithm can be equally successfully applied to any other emergency low-voltage situation.
The biochemical, physiological, and metabolic effects of Apollo nominal mission and contingency diets on human subjects while on a simulated Apollo mission Final report, Feb. - Jun. 1966
Biochemical, physiological, and metabolic effects of simulated Apollo mission with space diet on humans
An application of the multivariate extended Poisson distribution in 2 times 2 contingency tables Final report
Application of multivariate extended Poisson distributions
Launch site processing of hazardous payloads. Volume 4: Contingency processing analysis
Explore the source record for details and available documents.
Contingency plans for chromium utilization. Publication NMAB-335
The United States depends entirely on foreign sources for the critical material, chromium, making it very vulnerable to supply disruptions. The effectiveness of programs such as stockpiling, conservation, and research and development for substitutes to reduce the impact of disruption of imports of chromite and ferrochromium are discussed. Alternatives for decreasing chromium consumption also are identified for chromium-containing materials in the areas of design, processing, and substitution.