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Description: The LLNL inspection shop is chartered to make dimensional measurements of components for critical programmatic experiments. These measurements ensure that components are within tolerance and provide geometric details that can be used to further refine simulations. For these measurements to be useful, they must be significantly more accurate than the tolerances that are being checked. For example, if a part has a specified dimension of 100 millimeters and a tolerance of 1 millimeter, then the precision and/or accuracy of the measurement should be less than 1 millimeter. Using the ''10-to-1 gaugemaker's rule of thumb'', the desired precision of the measurement should be less than 100 micrometers. Currently, the process for associating measurement uncertainty with data is not standardized, nor is the uncertainty based on a thorough uncertainty analysis. The goal of this project is to begin providing measurement uncertainty statements with critical measurements performed in the inspection shop. To accomplish this task, comprehensive knowledge about the underlying sources of uncertainty for measurement instruments need to be understood and quantified. Moreover, measurements of elemental uncertainties for each physical source need to be combined in a meaningful way to obtain an overall measurement uncertainty.
Date: December 20, 2006
Creator: Nederbragt, W. W.
Partner: UNT Libraries Government Documents Department

Studies of non-proportionality in alkali halide and strontium iodide scintillators using SLYNCI

Description: Recently a collaboration of LLNL and LBNL has constructed a second generation Compton coincidence instrument to study the non-proportionality of scintillators. This device, known as SLYNCI (Scintillator Light-Yield Non-proportionality Characterization Instrument), has can completely characterize a sample with less than 24 hours of running time. Thus, SLYNCI enables a number of systematic studies of scintillators since many samples can be processed in a reasonable length of time. These studies include differences in nonproportionality between different types of scintillators, different members of the same family of scintillators, and impact of different doping levels. The results of such recent studies are presented here, including a study of various alkali halides, and the impact of europium doping level in strontium iodide. Directions of future work area also discussed.
Date: October 14, 2010
Creator: Ahle, Larry; Bizarri, Gregory; Boatner, Lynn; Cherepy, Nerine J.; Choong, Woon-Seng; Moses, William W. et al.
Partner: UNT Libraries Government Documents Department

Frontiers of Performance Analysis on Leadership-Class Systems

Description: The number of cores in high-end systems for scientific computing are employing is increasing rapidly. As a result, there is an pressing need for tools that can measure, model, and diagnose performance problems in highly-parallel runs. We describe two tools that employ complementary approaches for analysis at scale and we illustrate their use on DOE leadership-class systems.
Date: June 15, 2009
Creator: Fowler, R J; Adhianto, L; de Supinski, B R; Fagan, M; Gamblin, T; Krentel, M et al.
Partner: UNT Libraries Government Documents Department

Final Report for Time Domain Boundary Element and Hybrid Finite Element Simulation for Maxwell's Equations

Description: This report summarizes the work performed for Lawrence Livermore National Laboratory (LLNL) at the University of Washington between September 2004 and May 2006. This project studied fast solvers and stability for time domain integral equations (TDIE), especially as applied to radiating boundary for a massively parallel FEM solver.
Date: March 1, 2007
Creator: Pingenot, J & Jandhyala, V
Partner: UNT Libraries Government Documents Department

FY11 Level-2 Milestone 3953: TLCC2 contract awarded

Description: This report documents completion of FY11 L2 milestone No.3953-TLCC2 contract award. This milestone was scheduled for completion on 3/31/11 and was completed on 4/14/11. There is a separate milestone (3856), due at the end of the fiscal year, concerned with installation of the first LLNL SU and early user access. Efforts related to this tri-lab L2 milestone started early in 2010 with the development of tri-lab requirements for the second ASC capacity system procurement. The SOW was then developed along with necessary RFP paperwork and sent to HQ/DOE for their review prior to being released. There was significant delay in getting this step completed which led to this milestone being put at risk for several months. However, once the RFP was approved and released we were able to get the procurement back on track with aggressive proposal response and review timelines.
Date: September 12, 2011
Creator: Carnes, B
Partner: UNT Libraries Government Documents Department

FY07 Engineering Research and Technology Report

Description: This report summarizes the core research, development, and technology accomplishments in Lawrence Livermore National Laboratory's Engineering Directorate for FY2007. These efforts exemplify Engineering's more than 50-year history of developing and applying the technologies needed to support the Laboratory's national security missions. A partner in every major program and project at the Laboratory throughout its existence, Engineering has prepared for this role with a skilled workforce and technical resources developed through both internal and external venues. These accomplishments embody Engineering's mission: 'Enable program success today and ensure the Laboratory's vitality tomorrow'. Engineering's mission is carried out through research and technology. Research is the vehicle for creating competencies that are cutting-edge, or require discovery-class groundwork to be fully understood. The technology efforts are discipline-oriented, preparing research breakthroughs for broader application to a variety of Laboratory needs. The term commonly used for technology-based projects is 'reduction to practice'. This report combines the work in research and technology into one volume, organized into thematic technical areas: Engineering Modeling and Simulation; Measurement Technologies; Micro/Nano-Devices and Structures; Engineering Systems for Knowledge and Inference; and Energy Manipulation.
Date: February 6, 2008
Creator: Minichino, C
Partner: UNT Libraries Government Documents Department

LLNL Genomic Assessment: Viral and Bacterial Sequencing Needs for TMTI, Task 1.4.2 Report

Description: Good progress has been made on both bacterial and viral sequencing by the TMTI centers. While access to appropriate samples is a limiting factor to throughput, excellent progress has been made with respect to getting agreements in place with key sources of relevant materials. Sharing of sequenced genomes funded by TMTI has been extremely limited to date. The April 2010 exercise should force a resolution to this, but additional managerial pressures may be needed to ensure that rapid sharing of TMTI-funded sequencing occurs, regardless of collaborator constraints concerning ultimate publication(s). Policies to permit TMTI-internal rapid sharing of sequenced genomes should be written into all TMTI agreements with collaborators now being negotiated. TMTI needs to establish a Web-based system for tracking samples destined for sequencing. This includes metadata on sample origins and contributor, information on sample shipment/receipt, prioritization by TMTI, assignment to one or more sequencing centers (including possible TMTI-sponsored sequencing at a contributor site), and status history of the sample sequencing effort. While this system could be a component of the AFRL system, it is not part of any current development effort. Policy and standardized procedures are needed to ensure appropriate verification of all TMTI samples prior to the investment in sequencing. PCR, arrays, and classical biochemical tests are examples of potential verification methods. Verification is needed to detect miss-labeled, degraded, mixed or contaminated samples. Regular QC exercises are needed to ensure that the TMTI-funded centers are meeting all standards for producing quality genomic sequence data.
Date: January 26, 2010
Creator: Slezak, T; Borucki, M; Lam, M; Lenhoff, R & Vitalis, E
Partner: UNT Libraries Government Documents Department

Lessons learned at 208K: Towards Debugging Millions of Cores

Description: Petascale systems will present several new challenges to performance and correctness tools. Such machines may contain millions of cores, requiring that tools use scalable data structures and analysis algorithms to collect and to process application data. In addition, at such scales, each tool itself will become a large parallel application--already, debugging the full Blue-Gene/L (BG/L) installation at the Lawrence Livermore National Laboratory requires employing 1664 tool daemons. To reach such sizes and beyond, tools must use a scalable communication infrastructure and manage their own tool processes efficiently. Some system resources, such as the file system, may also become tool bottlenecks. In this paper, we present challenges to petascale tool development, using the Stack Trace Analysis Tool (STAT) as a case study. STAT is a lightweight tool that gathers and merges stack traces from a parallel application to identify process equivalence classes. We use results gathered at thousands of tasks on an Infiniband cluster and results up to 208K processes on BG/L to identify current scalability issues as well as challenges that will be faced at the petascale. We then present implemented solutions to these challenges and show the resulting performance improvements. We also discuss future plans to meet the debugging demands of petascale machines.
Date: April 14, 2008
Creator: Lee, G L; Ahn, D H; Arnold, D C; de Supinski, B R; Legendre, M; Miller, B P et al.
Partner: UNT Libraries Government Documents Department

Special-Status Plant Species Surveys and Vegetation Mapping at Lawrence Livermore National Laboratory

Description: This report presents the results of Jones & Stokes special-status plant surveys and vegetation mapping for the University of California, Lawrence Livermore National Laboratory (LLNL). Special-status plant surveys were conducted at Site 300 in April to May 1997 and in March to April 2002. Eight special-status plants were identified at Site 300: large-flowered fiddleneck, big tarplant, diamond-petaled poppy, round-leaved filaree, gypsum-loving larkspur, California androsace, stinkbells, and hogwallow starfish. Maps identifying the locations of these species, a discussion of the occurrence of these species at Site 300, and a checklist of the flora of Site 300 are presented. A reconnaissance survey of the LLNL Livermore Site was conducted in June 2002. This survey concluded that no special-status plants occur at the Livermore Site. Vegetation mapping was conducted in 2001 at Site 300 to update a previous vegetation study done in 1986. The purpose of the vegetation mapping was to update and to delineate more precisely the boundaries between vegetation types and to map vegetation types that previously were not mapped. The vegetation map is presented with a discussion of the vegetation classification used.
Date: October 3, 2006
Creator: Preston, R E
Partner: UNT Libraries Government Documents Department

Sample Proficiency Test exercise

Description: The current format of the OPCW proficiency tests has multiple sets of 2 samples sent to an analysis laboratory. In each sample set, one is identified as a sample, the other as a blank. This method of conducting proficiency tests differs from how an OPCW designated laboratory would receive authentic samples (a set of three containers, each not identified, consisting of the authentic sample, a control sample, and a blank sample). This exercise was designed to test the reporting if the proficiency tests were to be conducted. As such, this is not an official OPCW proficiency test, and the attached report is one method by which LLNL might report their analyses under a more realistic testing scheme. Therefore, the title on the report ''Report of the Umpteenth Official OPCW Proficiency Test'' is meaningless, and provides a bit of whimsy for the analyses and readers of the report.
Date: February 5, 2006
Creator: Alcaraz, A; Gregg, H & Koester, C
Partner: UNT Libraries Government Documents Department

Simulations of the 1906 San Francisco Earthquake

Description: Simulations of the Great 1906 San Francisco earthquake are being performed as part of the event's centenary. LLNL is participating in a large effort to study this event and possible consequences if the event were to happen today. This document is meant to describe our efforts to others participating in the project.
Date: December 16, 2005
Creator: Rodgers, A; Petersson, A & Tkalcic, H
Partner: UNT Libraries Government Documents Department

MIDAS (Material Implementation, Database, and Analysis Source): A comprehensive resource of material properties

Description: MIDAS is aimed to be an easy-to-use and comprehensive common source for material properties including both experimental data and models and their parameters. At LLNL, we will develop MIDAS to be the central repository for material strength related data and models with the long-term goal to encompass other material properties. MIDAS will allow the users to upload experimental data and updated models, to view and read materials data and references, to manipulate models and their parameters, and to serve as the central location for the application codes to access the continuously growing model source codes. MIDAS contains a suite of interoperable tools and utilizes components already existing at LLNL: MSD (material strength database), MatProp (database of materials properties files), and MSlib (library of material model source codes). MIDAS requires significant development of the computer science framework for the interfaces between different components. We present the current status of MIDAS and its future development in this paper.
Date: December 13, 2010
Creator: Tang, M; Norquist, P; Barton, N; Durrenberger, K; Florando, J & Attia, A
Partner: UNT Libraries Government Documents Department

UTag: Long-range Ultra-wideband Passive Radio Frequency Tags

Description: Long-range, ultra-wideband (UWB), passive radio frequency (RF) tags are key components in Radio Frequency IDentification (RFID) system that will revolutionize inventory control and tracking applications. Unlike conventional, battery-operated (active) RFID tags, LLNL's small UWB tags, called 'UTag', operate at long range (up to 20 meters) in harsh, cluttered environments. Because they are battery-less (that is, passive), they have practically infinite lifetimes without human intervention, and they are lower in cost to manufacture and maintain than active RFID tags. These robust, energy-efficient passive tags are remotely powered by UWB radio signals, which are much more difficult to detect, intercept, and jam than conventional narrowband frequencies. The features of long range, battery-less, and low cost give UTag significant advantage over other existing RFID tags.
Date: March 14, 2007
Creator: Dowla, F.
Partner: UNT Libraries Government Documents Department

UCom: Ultra-wideband Communications in Harsh Propagation Environments

Description: LLNL has developed an ultra-wideband (UWB) system that provides unique, through-the-wall wireless communications in heavy metallic and heavy concrete indoor channels. LLNL's UWB system is the only available wireless communications system that performs successfully and reliably in facilities where conventional narrowband communications usually fail due to destructive reflections from multiple surfaces. These environments include: cargo ships and reinforced, heavy concrete buildings. LLNL's revolutionary system has applications for the military, as well as commercial indoor communications in multistory buildings, and cluttered industrial structures.
Date: March 14, 2007
Creator: Nekoogar, F
Partner: UNT Libraries Government Documents Department

Excited Spectator Electron Effects on Spectral Line Shapes

Description: Excited spectator electron effects on Stark broadened spectral line shapes of transitions involving tightly bound electrons are investigated. It is shown that the interference terms in the electron impact broadening are essential to describe the overlapping lines generated by these configurations (e.g.; dielectronic satellite lines). The main impact is narrower spectral features and reduced far wing intensities compared to calculations neglecting the interference terms.
Date: October 12, 2009
Creator: Iglesias, C A
Partner: UNT Libraries Government Documents Department