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The first meeting that became the International Conference on Nuclear Criticality—ICNC—was held at the Los Alamos National Laboratory in February 1981. This presentation includes information on that meeting, including several experiments performed around that time period.
The objective of this project was to develop relationships between published scholarship, industry experience, and remanufacturing design rules and identify a clear path for integrating remanufacturing design rules into CAD tools and design practices. To accomplish this, remanufacturing knowledge was compiled, and then the relationships between this knowledge and a prioritized set of product design guidelines was developed. Next, a process to create rules out of guidelines was developed by first defining life extension as a primary function, and remanufacturing as effective tasks to control the failure modes that would restrict the product life. The reliability centered maintenance (RCM) process was used to identify proactive tasks and default actions to mitigate the effects of failure modes. These tasks were developed into expert system rules. The impact of design on remanufacturing was then validated through implementing a prioritized set of design rules for a Heavy Duty Off-Road (HDOR) techno-economic case study. Finally, detailed steps on how to define, develop, and integrate these rules into CAD were created.
EPRDATA in MCNP comes in 2 libraries, EPRDATA12 and EPRDATA14. The acronym EPR stands for Electron Photon, and atomic Relaxation. The libraries are in an extended form of the ACE format. This extended data includes more physics than the more common MCPLIB photo-atomic libraries, such as MCPLIB63 and MCPLIB84.
The CSEWG covariance session template paper was submitted on June 8, 2021 to journal. CSEWG will not publish adjusted VIII.1, but there is interest in adjustment results from the community. Other focus points for the release for VIII.1 include stringent testing of covariances before their release and missing covariances.
The mission of the Nuclear Criticality Safety Program is to provide sustainable expert leadership, direction and the technical infrastructure necessary to develop, maintain, and disseminate the essential technical tools, training, and data required to support safe, efficient fissionable material operations within DOE; the vision of the program is a Continually improving, adaptable, and transparent program that communicates and collaborates globally to incorporate technology, practices, and programs to be responsive to the essential technical needs of those responsible for developing, implementing, and maintaining nuclear criticality safety. Training and education topics for the program include a 1-week Manager/Criticality Safety Officer Course and a 2-week NCS Engineer Hands-on Training Course.
The modernization of SAMMY continued with consolidation of access to covariance information for adjusted parameters and data in SAMMY. This consolidation allowed for removal of many scratch files. In addition, work was initiated to make the 0K cross section calculation more modular and less dependent on SAMMY global parameters. An initial application programming interface (API) was added to expose cross sections (including resolution broadening) generated by SAMMY to external fitting routines. The processing for thermal moderators in AMPX was updated for selected moderators for which the generated grid was not fine enough. Updated libraries were generated for SCALE. In addition, work continued to fully support new Evaluated Nuclear Data File (ENDF) formats, including the Generalized Nuclear Database Structure (GNDS) in AMPX.
This SAND Report Guide offers support to authors, technical writers, principal investigators, and others involved in the process of creating, formatting, or refining a SAND Report. It details what you need to know before you begin compiling a SAND Report, directs you to the SAND Report templates, outlines the order of elements in a SAND Report, and explains what to do when your report is completed and ready for Review and Approval and subsequent distribution. Supporting information is provided in the appendix, such as where to get technical assistance, trademarks, Microsoft Word, and equations.
The purpose of this note is to draw attention to Pál for his derivation of the Pál-Bell equation which is used by LLNL and LANL to model Probability of Initiation (POI) problems. Both laboratories credit the equation to Bell and Lee. Although the equation formulated by Bell and Lee and the equation derived by Pál appear to be the same, the equation by Bell and Lee is flawed. Scattering, which was absent in Bell’s original formulation of a POI problem, was later introduced by Bell and Lee by replacing a fission term with a scattering term. Such a replacement, however, leads to an incorrect average number $\overline{v}$ of neutrons that is produced in a fission event. By approaching a POI problem from probabilistic point of view, Pál formulates the problem as a branching process that i) describes the growth of a population of neutrons in a fissile medium, and ii) predicts $\overline{v}$ correctly. There are five reasons for writing this report. The first is to clarify the failing in Bell and Lee’s derivation. The second is to establish the origin of the equation used by the laboratories. The third is to elucidate the fixed point technique formulated by Mokhtar-Kharroubi to solve the Pál-Bell equation. The fourth is to derive the α eigenvalue that is associated with a super-critical situation. The fifth is to describe in the Appendix a second order positivity preserving technique that accelerates the convergence of the first order fixed point method developed by Mokhtar-Kharroubi.
The Transportation Energy Data Book: Edition 40 is a statistical compendium prepared and published by Oak Ridge National Laboratory (ORNL) under contract with the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Vehicle Technologies Office. Designed for use as a desk-top reference, the Data Book represents an assembly and display of statistics and information that characterize transportation activity and presents data on other factors that influence transportation energy use. The purpose of this document is to present relevant statistical data in the form of tables and graphs. The latest edition of the Data Book is available via the Internet (tedb.ornl.gov).This edition of the Data Book has 13 chapters which focus on various aspects of the transportation industry. Chapter 1 focuses on petroleum; Chapter 2 – energy; Chapter 3 – highway vehicles; Chapter 4 – light vehicles; Chapter 5 – heavy vehicles; Chapter 6 – alternative fuel vehicles; Chapter 7 – transit and other shared mobility; Chapter 8 – fleet vehicles; Chapter 9 – household vehicles; Chapter 10 – nonhighway modes; Chapter 11 – transportation and the economy; Chapter 12 – greenhouse gas emissions; and Chapter 13 – criteria pollutant emissions. The sources used represent the latest available data. There are also two appendices which include detailed source information for some tables and measures of conversion. A glossary of terms is also included for the reader’s convenience.
Abstract not provided.
This document is intended to serve as a guide for the review of records in LANL’s Weapons Materials Database. Specifically, this guide provides step-by-step instructions for the review of records associated with a materials testing project. This is the type of dataset that testing organizations such as MST-7 & MST-8 at LANL commonly produce for the weapons complex and want to archive in Granta:MI.
During the COVID-19 pandemic of 2020, major case reporting outlets quickly coalesced around two or three primary vendors. Johns Hopkins University and The New York Times were among the more prominent, and all were of great value to the nation, particularly during the uncertain early stages of the pandemic. They primarily focused on three major attributes: number of new cases, deaths, and recovery, but only at the state level. Recognizing that many states were reporting very detailed data sets (e.g., hospital beds) at a count level or finer, the ORNL Pandemic Modeling team embarked on a major data curation effort from March to June 2020 for the purpose of capturing this wealth of detailed data. The challenge of curating this data was daunting. The number of attributes reported by the states grew on almost on a weekly basis. States were routinely shifting their web tool strategies away from easily parsable HTML-based formatting to new Tableau and ArcGIS content. This growth in the sheer number of attributes combined with the unpredictable shifts in data format meant an aggressive and agile combination of automated scripting and manual scraping was required to capture new daily streams. To keep up, the team had to scale up staff and widen its approach for capture and storage. The DOE COVID-19 data collection effort resulted in over 11 million data points being collected, covering over 13,000 unique geographies and over 2,000 unique attributes that spanned predominantly from early March through the end of June 2020.
Join Senior Historian Alan Carr as he presents “Introduction to Nuclear Weapons Testing, 1945 to 1992” in commemoration of the 30th anniversary of the nation’s last full-scale nuclear test. Special guest retired Los Alamos test director Ron Cosimi will offer the opening remarks. Attendees will receive an original commemorative poster and can browse a new, temporary Divider test display.
This report provides basic information about Divider, the nation's last full-scale weapons test and how to get a commemorative poster marking the 30th anniversary.
Document details key information about the Nuclear Criticality Safety Program (NCSP) including financial data, functions and execution of the program, and accomplishments, challenges, and initiatives, as well as projected projects/accomplishments.
Nuclear Data Team at LANL is working to improve nuclear data availability. These efforts include an updated, modernized, and improved website and a new, dynamic tool for examining what ACE data is on your machine.
The project objective and motivation is to develop thermal data libraries for selected isotopes in MCNP6 to support on-the-fly S(alpha, beta) sampling for temperature ranges applicable to nuclear criticality safety, thereby enhancing the physics treatment in MCNP6 so that it can perform fast on-the-fly sampling of S(alpha, beta) data at arbitrary temperature.
This presentation highlights the activities of Los Alamos National Laboratory (LANL) in fiscal year 2021.These include the celebration of the tenth anniversary of NCERC operations, a large experiment campaign (IER 488 - MUSiC: Measurements of Uranium Subcritical and Critical), preparation for FY22 experiments, the completion of several ongoing experiments, and a control system upgrade project.