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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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Uncertainty quantification in the machine-learning inference from neutron star probability distribution to the equation of state
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Low-shot, Semi-supervised, Uncertainty Quantification Enabled Model for High Consequence HSI Data.
Abstract not provided.
Analytical Data-Driven Method for Geomagnetic Disturbance Uncertainty Quantification Compensation
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Uncertainty Quantification in Stochastic Economic Dispatch using Gaussian Process Emulation
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Debiased Uncertainty Quantification Approach for Probabilistic Transient Stability Assessment
Not provided.
Data-Driven Uncertainty Quantification for Multisensor Analytics.
Abstract not provided.
A General Framework of Rotational Sparse Approximation in Uncertainty Quantification
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Using Data-Driven Uncertainty Quantification to Support Decision Making.
Abstract not provided.
Uncertainty Quantification for Electronic Hamiltonian
This program will generate random points for electrons within the dimensions given by a parameter input file. Based on these randomly generated electron positions and the nuclear positions given by a position input file it will generate a value for the total electronic energy of an isolated system. This total electronic energy is calculated using the electronic Hamiltonian for a monoatomic system with atoms having the same number of protons and neutrons. The size of the system is defined by the parameter input file. The program will do this many times to generate a distribution of theoretically possible electronic total energies of the system. A user can then compare the total electronic energy given by their electronic structure method to make sure it falls within the distribution of theoretically possible values.
Seismic inversion and uncertainty quantification using transdimensional Markov chain Monte Carlo method
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Stochastic analog neutron transport with TRIPOLI-4 and FREYA: Bayesian uncertainty quantification for neutron multiplicity counting
From nuclear safeguards to homeland security applications, the need for the better modeling of nuclear interactions has grown over the past decades. Current Monte Carlo radiation transport codes compute average quantities with great accuracy and performance; however, performance and averaging come at the price of limited interaction-by-interaction modeling. These codes often lack the capability of modeling interactions exactly: for a given collision, energy is not conserved, energies of emitted particles are uncorrelated, and multiplicities of prompt fission neutrons and photons are uncorrelated. Many modern applications require more exclusive quantities than averages, such as the fluctuations in certain observables (e.g., the neutron multiplicity) and correlations between neutrons and photons. In an effort to meet this need, the radiation transport Monte Carlo code TRIPOLI-4® was modified to provide a specific mode that models nuclear interactions in a full analog way, replicating as much as possible the underlying physical process. Furthermore, the computational model FREYA (Fission Reaction Event Yield Algorithm) was coupled with TRIPOLI-4 to model complete fission events. As a result, FREYA automatically includes fluctuations as well as correlations resulting from conservation of energy and momentum.
Monte Carlo Uncertainty Quantification in UF 6 Cylinder Neutron Emissions
In order to provide timely detection of the diversion of nuclear material, the international community needs to develop technology for safeguarding the entire fuel cycle. As such, there is significant interest in securing the front end of the fuel cycle through precise and accurate material accountancy prior to fuel irradiation. One particularly attractive solution for such problems is the development of unattended enrichment verification monitors for uranium hexafluoride (UF 6 ) transit cylinders. Systems such as the Unattended Cylinder Verification Station (UCVS) promise to provide independent nuclear material accountancy (i.e. measurements of relative enrichment, 235 U mass and total uranium mass) for all UF 6 cylinders entering and/or leaving any enrichment or fuel fabrication facilities.