Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “GNDS”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

GNDS v2.0 release and future developments [Slides]

This presentation begins by discussing the major changes in v2.0 of GNDS and that the GNDS-2.0 formatted libraries are now available. It also examines how code support for GNDS is growing with processing codes, APIs and transport codes, and evaluation/testing codes. The presentation states that while migrating to GNDS can be a major effort it worthwhile, especially for anyone who is just getting started as nuclear data creator or user. Additionally, this presentation outlines the established milestones that the EG-GNDS (the group in charge of GNDS specs) has for the next GNDS release and elaborates on the first goal, which is to migrate GNDS specifications to the new JSON schema language.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2020

GNDS Expert Group Report [Slides]

The presentation discusses the GNDS-1.9 specifications that were published during the Summer 2020 and a webinar that occurred on 8 July 2020. It also discusses the goals of the GNDS-2.0, including the intention to satisfy the remaining SG-38 goals, to ensure “forwards compatibility” with ENDF-6, and to respond to user needs. It discusses the 2020 status and a poll that was implemented to find out more about how GNDS is being implemented. The presentation states that some projects are far along in their GNDS support and that most are open source with 20% closed source. It also states that GNDS's purpose is to inspire younger scientists with a histogram displaying what fraction of the developers are student, post-docs, and junior staff. The presentation concludes by discussing what is next including major format changes post-GNDS-2.0 and an ENDF to GNDS transition.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2018

Testing of ENDF/B-VIII.0 in the GNDS format with LLNL transport codes - 25606

ENDF/B-VIII.0 was released in the Evaluated Nuclear Data Format and the Generalized Nuclear Data Structure format (GNDS), a new international standard for storing nuclear data developed under the auspices of the Nuclear Energy Agency Working Party on Evaluation Cooperation Subgroup 38. GNDS relies on modern coding practices, and offers a structured, flexible and physics-based standard for storing and exchanging nuclear data to address limitations in legacy nuclear data formats such as ENDF-6. GNDS supports the storage of evaluated nuclear data as well as processed data suitable for both deterministic (i.e., multi-group) and Monte Carlo transport codes. Lawrence Livermore National Laboratory has implemented a complete suite of codes to test GNDS data. Simulations for the ENDF/B-VIII.0 cross-section library in GNDS format are presented. Deterministic and Monte Carlo radiation transport simulations with the Ardra and Mercury codes respectively, are validated against reactivities in fast criticality safety benchmark assemblies. Finally, Mercury simulations of {sup 238}U(n,f), {sup 237}Np(n,f) and {sup 239}Pu(n,f) reaction rates in Godiva, Jezebel and Flattop are compared to MCNP results and measured data. (authors)

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2022

The LLNL nuclear data infrastructure for the GNDS data format

The next generation of nuclear data infrastructure tools at the Livermore National Laboratory (LLNL) consists of pipeline of codes that read and process nuclear data from evaluated files saved in the new GNDS (Generalised Nuclear Data Structure) nuclear data format. The processing code FUDGE (For Updating Data and Generating Evaluations) is at the front-end of this pipeline as it reads and process the evaluated data for use in downstream transport codes. FUDGE is Python based with C and C++ extensions for computationally intensive tasks. As is the case for the evaluated data, the processed output is also saved in the GNDS format and the GIDI+ API is provided as the interface between the processed data and the transport codes. GIDI+ is a C++ based suite of codes and it includes GIDI (General Interaction Data Interface), a library for reading and writing GNDS data, and MCGIDI which is the cross section lookup, and reaction and product distribution sampling interface between Monte Carlo transport codes and the GNDS data. GIDI provides methods for easy access to the multi-group processed GNDS data and this is demonstrated through its implementation in ARDRA, the LLNL deterministic transport code. The evaluation and sampling methods in MCGIDI are available as both CPU and GPU methods which facilitates the use of MCGIDI in both traditional CPU-based as well as the next generation mixed model computational architectures. This is demonstrated through the GIDI+ implementation in MERCURY, the LLNL Monte Carlo transport code. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2025

Progress Towards International GNDS Adoption [Slides]

This presentation includes a GNDS quick overview. Libraries are increasingly available in GNDS as well as ENDF-6, Multiple evaluation / processing / checking / visualization codes have begun to support GNDS. LLNL codes FUDGE and GIDIplus are open-source tools for creating, processing and using GNDS.

Generalised Nuclear Database Structure (GNDS)↗
DOE OSTI2022

TNSL support in GNDS 2.0 and beyond [Slides]

This presentation begins by discussing the TNSL format options that went through a major overhaul in GNDS-2.0 and it examines the changes in 2.0. Additionally, it discusses three issues with further changes that should be considered. The first issue is that the project needs some guidance on what to expect when evaluations are performed with coherent inelastic. The second issue is that GNDS-2.0 does not provide a way to clearly specify in the evaluation how to switch to ‘standard’ incident neutron evaluations for energies or temperatures outside the TNSL domain. The third issue is that when GNDS-2.0 was designed, it was assumed that S(α,β) would always be given on a uniform interpolation grid. The presentation concludes by discussing how New JENDL-5 TNSL evaluations have some complications.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2023

Status of GNDS Support in AMPX [Slides]

This presentation covers the status of GNDS Support in AMPX. This presentation covers an overview of GNDS support in AMPX. Then the presentation touches on the AMPX process in GNDS and a checklist. This presentation concludes with a continuing effort section and conclusions.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2024

AMPX Support for GNDS-2.1 [Slides]

This presentation is a review of AMPX strategy for GNDS. It includes a summary of point data comparison, Summary of covariance data comparison, and a preview of SAMMY GNDS I/O and other development.

ENDF↗
DOE OSTI2024

Legacy (NDF & MCF), GNDS and Direct forms of the ENDL2009.5 Evaluated Nuclear Data Library

The ENDL2009.5 Evaluated Nuclear Data Library is now available three different processed forms for users: (1) the Legacy form using NDF and MCF processing of the ENDL files, (2) the GNDS form which uses FUDGE and Merced to process the translations in to GNDS of the ENDL files, and (3) the Direct form which uses FUDGE and Merced to process where available the original ENDF6- format source files used to make the ENDL files. If original files are not available for various protares in the Direct form, then the ENDL forms are used.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2022

Status of GNDS support in AMPX [Slides]

This presentation provides an overview of ENDF reading in AMPX, as well as information regarding low level access classes for GNDS used in AMPX and the use of these classes in AMPX and SAMMY.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2022

Comparison of URR Implementations in GNDS Format [Slides]

LLNL implemented infrastructure to include treatment of URR in GNDS. There are two options to store URR probabilities: cross-sections pdf and ACE-like probability tables. Issues were found with both options during verification with criticality benchmarks. Projected future steps include resolving issues in the next year and adding criticality benchmarks sensitive to URR.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗