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Results for “Uncertainty Quantification”

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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At least 559 records · Page 31
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

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.

Savchick, JuniperC↗
DOE OSTI2019

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.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2018

Enhanced Analytical Simulation Tool (EASiTool) for CO 2 Storage Capacity Estimation and Uncertainty Quantification

An enhanced analytical simulation tool (EASiTool) was developed to estimate CO 2 storage capacity in saline aquifers. The tool provides a quantitative estimate of storage capacity for multi-well injection/extraction systems by applying novel analytical models for both closed- and open-boundary saline aquifers and analyzes the potential of enhancing storage efficiency by integrating active brine management (brine extraction technology). Brine extraction would enhance the storage capacity and partially control the pressure buildup. EASiTool includes a user-friendly interface and can be used to provide reservoir and basin-scale storage capacity estimates.

58 GEOSCIENCES↗
DOE OSTI2018

Sensitivity Analysis and Uncertainty Quantification of the Feynman Y and Sm 2

Neutron multiplicity counting (NMC) experiments are frequently used to perform non-destructive assay (NDA) of special nuclear material (SNM) [2]. While the behavior of a critical or nearly critical system is well described by the mean count rate, which is the mean of the NMC distribution, the behavior of a highly subcritical system exhibits large fluctuation in time. Fission chains do not last long enough to overlap and thus the neutron population is relatively small with a large dispersion. The system behavior must therefore be described in terms of higher-order NMC distribution moments.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗