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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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Latest News
What’s the most difficult question you’ve been asked as a maintenance instructor?
Blye Widmar
"Where are the prints?!"
This was the final question in an onslaught of verbal feedback, comments, and critiques I received from my students back in 2019. I had two years of instructor experience and was teaching a class that had been meticulously rehearsed in preparation for an accreditation visit. I knew the training material well and transferred that knowledge effectively enough for all the students to pass the class. As we wrapped up, I asked the students how they felt about my first big system-level class, and they did not hold back.
“Why was the exam from memory when we don’t work from memory in the plant?” “Why didn’t we refer to the vendor documents?” “Why didn’t we practice more on the mock-up?” And so on.
Ivan Kodeli
Nuclear Science and Engineering | Volume 138 | Number 1 | May 2001 | Pages 45-66
Technical Paper | doi.org/10.13182/NSE00-43
Articles are hosted by Taylor and Francis Online.
In the nuclear industry, an increased demand exists to provide modeling results with credible confidence bounds not only for simple but also for refined modeling. With the objective to facilitate and promote such analysis, a user-friendly and complete computer code package was developed comprising the multidimensional cross-section sensitivity and uncertainty code package SUSD3D, the secondary angular distribution (SAD) covariance data-processing module ERRORR34, and the cross-section covariance matrix library ZZ-VITAMIN-J/COVA.The discrete ordinates sensitivity formulation of the first-order perturbation theory is implemented in the SUSD3D code. Much effort was devoted to mitigate some drawbacks of the discrete ordinates-based sensitivity analysis, in particular to allow the analysis of complex geometries and to reduce memory requirements. The SUSD3D code is linked via interface files to a wide range of state-of-the-art transport codes suitable for complex radiation transport and facility design studies (like ANISN, DOT-3.5, DANTSYS, DORT, and TORT) and supports the new cross-section and covariance data formats. The SAD and secondary energy distribution effects can be taken into account. The complete SAD covariance matrices, as available in the European Fusion File evaluations (EFF-2 and -3) can be treated. The computer codes are written in FORTRAN-77 and run under DOS (PC), UNIX (workstations), VMS (VAX), and other compatible operating systems.The code system is extensively used to study fission- and fusion-related problems. The validation and several practical applications of the package are presented, including the reactor pressure vessel surveillance uncertainty studies, and ASPIS-iron, VENUS-3, and FNG benchmark experiment analyses.