Engineering topics

Shugart, Nicolas

Publications and source records attributed to Shugart, Nicolas.

3 records

DOE OSTI2018

Optimizing Nuclear Material Accounting and Measurement Systems

The ability to create nuclear weapons from 235 U and 239 Pu makes it imperative to closely account for these materials as they progress through a nuclear fuel cycle. Improved measurement systems provide more accurate estimates of material quantities and material unaccounted for (MUF). This work provides examples of how two safeguards computational toolboxes can optimize and analyze hypothetical nuclear fuel cycle scenarios. The NUclear Measurement System Optimization (NUMSO) toolbox uses operations research techniques to find optimal solutions to safeguards measurement problems based on minimizing the variance of the estimated MUF. The SafeGuards Analysis (SGA) toolbox employs Monte Carlo techniques to analyze a given configuration of measurement methods and material flows to determine the probabilities of Type I (false detection) and Type II (missed detection) errors. Applying these toolboxes to a realistic fuel cycle scenario demonstrates the capability of NUMSO and SGA to address nuclear safeguards problems. Working in tandem, both toolboxes are able to determine how to quickly improve upon an existing safeguards measurement system and to calculate the resulting improvement in the error probabilities of the system. This information shows engineers not only how to develop new measurement systems but also how to improve existing systems in the most efficient manner.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2018

Examining Fuel-Cycle Scenarios with the Safeguards Analysis Toolbox

SafeGuards Analysis (SGA) is a toolbox developed to allow engineers and scientists to create detailed simulations of safeguards material control and accountability simulations. SGA accepts material flow data from an external material flow model, and can be used with any existing fuel cycle or material control code. This work examines some new developments to the SGA code that allow the code to consider material losses over long timeframes. The first scenario described in this paper examined an enrichment facility consisting of two material balance areas (MBAs). Cumulative sum and basic control chart tests evaluate to a case involving a loss of material from both MBAs simultaneously and a case in which material is removed from the facility over a timescale of double the one that the tests were calibrated to detect. A second scenario represents an entire fuel-cycle consisting of four MBAs and two materials of interest (low-enriched uranium and plutonium). This scenario evaluated the calibrated safeguards system with three blind unidentified stream cases, with the goal of determining the calibrated system’s ability to detect where the material loss occurred in each case. SGA was able to produce the expected results for all of the examples examined in this paper, demonstrating that modules produced using the toolbox are capable of examining larger systems in realistic multi-MBA scenarios.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2018

SafeGuards Analysis

The SafeGuards Analysis (SGA) toolkit is an add-on to existing fuel cycle codes that provides safeguards measurement and evaluation modeling capabilities with associated uncertainty quantification and sensitivity analysis techniques. An important feature of the SGA toolbox is that any other fuel cycle or facility-level code (such as VISION, CYCLUS, et al.) can be easily modified to work with SGA. Thus SGA can incorporate any of the other available fuel cycle codes with minimal modification.

Shugart, Nicolas↗