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Convergence Analysis of a Domain Decomposition Paradigm

Description: We describe a domain decomposition algorithm for use in several variants of the parallel adaptive meshing paradigm of Bank and Holst. This algorithm has low communication, makes extensive use of existing sequential solvers, and exploits in several important ways data generated as part of the adaptive meshing paradigm. We show that for an idealized version of the algorithm, the rate of convergence is independent of both the global problem size N and the number of subdomains p used in the domain decomposition partition. Numerical examples illustrate the effectiveness of the procedure.
Date: June 12, 2006
Creator: Bank, R E & Vassilevski, P S
Partner: UNT Libraries Government Documents Department

Science into art: A study of the creative process

Description: Objective was to examine the creative process, demonstrated by 5 student participants in a class at the Art Center College of Design in Pasadena CA, from the germ of the creative idea through the final creative product. The students, drawn from classes sponsored by LLNL, were assigned the problem of representing ``big`` science, as practiced at LLNL, in a graphic, artistic, or multimedia product. As a result of this study, it was discovered that the process of creativity with these students was not linear in nature, nor did it strictly follow the traditional creativity 5-step schema of preparation, incubation, insight, evaluation, and elaboration. Of particular interest were several emergent themes of the creative process: spontaneous use of metaphor to describe the Laboratory; a general lack of interest in ``school`` science or mathematics by the American art students; a well developed sense of conscience; and finally, the symbolism inherent in the repeated use of a single artistic element. This use of the circle revealed a continuity of thinking and design perhaps related to the idealistic bias mentioned above.
Date: March 14, 1997
Creator: Marchant, M. & Sesko, S.C.
Partner: UNT Libraries Government Documents Department

FY10 Engineering Innovations, Research and Technology Report

Description: This report summarizes key research, development, and technology advancements in Lawrence Livermore National Laboratory's Engineering Directorate for FY2010. These efforts exemplify Engineering's nearly 60-year history of developing and applying the technology innovations needed for the Laboratory's national security missions, and embody Engineering's mission to ''Enable program success today and ensure the Laboratory's vitality tomorrow.'' Leading off the report is a section featuring compelling engineering innovations. These innovations range from advanced hydrogen storage that enables clean vehicles, to new nuclear material detection technologies, to a landmine detection system using ultra-wideband ground-penetrating radar. Many have been recognized with R&D Magazine's prestigious R&D 100 Award; all are examples of the forward-looking application of innovative engineering to pressing national problems and challenging customer requirements. Engineering's capability development strategy includes both fundamental research and technology development. Engineering research creates the competencies of the future where discovery-class groundwork is required. Our technology development (or reduction to practice) efforts enable many of the research breakthroughs across the Laboratory to translate from the world of basic research to the national security missions of the Laboratory. This portfolio approach produces new and advanced technological capabilities, and is a unique component of the value proposition of the Lawrence Livermore Laboratory. The balance of the report highlights this work in research and technology, organized into thematic technical areas: Computational Engineering; Micro/Nano-Devices and Structures; Measurement Technologies; Engineering Systems for Knowledge Discovery; and Energy Manipulation. Our investments in these areas serve not only known programmatic requirements of today and tomorrow, but also anticipate the breakthrough engineering innovations that will be needed in the future.
Date: January 11, 2011
Creator: Lane, M A; Aceves, S M; Paulson, C N; Candy, J V; Bennett, C V; Carlisle, K et al.
Partner: UNT Libraries Government Documents Department

Inertial Confinement Fusion: Quarterly report, April-June 1996

Description: The lead article, `Ion-beam propagation in a low-density reactor chamber for heavy-ion inertial fusion` (p. 89), explores the ability of heavy-ion beams to be adequately transported and focused in an IFE reactor. The next article, `Efficient production and applications of 2- to 10-keV x rays by laser-heated underdense radiators` (p. 96), explores the ability of the NIF to produce sufficient high-energy x rays for diagnostic backlighting, target preheating, or uniform irradiation of large test objects for Nuclear Weapons Effects Testing. For capsule implosion experiments, the increasing energies and distances involved in the NIF compared to Nova require the development of new diagnostics methods. The article `Fusion reaction-rate measurements--Nova and NIF` (p. 115) first reviews the use of time-resolved neutron measurements on Nova to monitor fusion burn histories and then explores the limitations of that technique, principally Doppler broadening, for the proposed NIF. It also explores the use of gamma rays on Nova, thereby providing a proof-of-principle for using gamma rays for monitoring fusion burn histories on the NIF. The articles `The energetics of gas-filled hohlraums` (p. 110) and `Measurements of laser- speckle-induced perturbations in laser-driven foils` (p. 123) report measurements on Nova of two important aspects of implosion experiments. The first characterizes the amount of energy lost from a hohlraum by stimulated Brillouin and Raman scattering as a function of gas fill and laser-beam uniformity. The second of these articles shows that the growth of density nonuniformities implanted on smooth capsule surfaces by laser speckle can be correlated with the effects of physical surface roughness. The article `Laser-tissue interaction modeling with the LATIS computer program` (p. 103) explores the use of modeling to enhance the effectiveness--maximize desired effects and minimize collateral damage--of lasers for medical purposes.
Date: June 1, 1996
Creator: Correll, D.
Partner: UNT Libraries Government Documents Department

Testing and diagnostic capabilities at LLNL

Description: Testing activities today at LLNL occur at three different locations: Livermore, Site 300, and the Nevada Test Site. At the Livermore location, there are three gas guns, two of which are used primarily for materials studies and scientific experiments on materials. The third gun is located in the High Explosive Applications Facility (HEAF) and fires into a chamber rated for 10 kg of explosive containment. The HEAF gun is used primarily for impact studies on explosives. Also within HEAF are five other containment chambers for explosive testing. Each is instrumented to varying degrees to supply the necessary information of explosive behavior. These include high speed optics, Fabry Perot velocimetry and radiography. The descriptions of the three gas guns and a summary of the HEAF facility are presented in the accompanying figures.
Date: September 24, 1998
Creator: Baum, D W
Partner: UNT Libraries Government Documents Department

Science/art - art/science: case studies of the development of a professional art product

Description: Objective was to follow the cognitive and creative processes demonstrated by student research participants as they integrated a developing knowledge of ``big`` science, as practiced at LLNL, into a personal and idiosyncratic visual, graphical, or multimedia product. The participants, all non-scientists, involved in this process, attended a series of design classes, sponsored by LLNL at the Art Center College of Design in Pasadena CA. As a result of this study, we have become interested in the possibility of similar characteristics between scientists and artists. We have also become interested in the different processes that can be used to teach science to non-scientists, so that they are able to understand and portray scientific information.
Date: February 24, 1997
Creator: Sesko, S.C. & Marchant, M.
Partner: UNT Libraries Government Documents Department

Summary of personal monitoring data for asbestos-related maintenance work at the Lawrence Livermore National Laboratory

Description: The Lawrence Livermore National Laboratory (LLNL) consists of 665 structures with approximately 6 million square feet of space. Many of the buildings date from the 1940`s to 1980`s and contain asbestos-containing materials (ACM). Maintenance and Operation activities, as well as full scale asbestos abatement and repair, has been conducted for many years. One result of all this activity is that a substantial database of personal monitoring data has been collected. This database is a collection of reported (Fed OSHA) Permissible Exposure Limit (PEL) information, including 8-hour Time Weighted Averages (TWA) and 30-minute Excursion Limit (EL) samples. Because this data represented a wide variety of asbestos removal techniques, materials and sampling strategies and industrial hygienists, a rigorous statistical comparison is of limited value. By summarizing the data by procedure category, procedures likely to result in significant exposures can be identified.
Date: May 1996
Creator: Franaszek, S. M. & Kelly, R. J.
Partner: UNT Libraries Government Documents Department

Remotely controlled reagent feed system for mixed waste treatment Tank Farm

Description: LLNL has developed and installed a large-scale. remotely controlled, reagent feed system for use at its existing aqueous low-level radioactive and mixed waste treatment facility (Tank Farm). LLNL`s Tank Farm is used to treat aqueous low-level and mixed wastes prior to vacuum filtration and to remove the hazardous and radioactive components before it is discharged to the City of Livermore Water Reclamation Plant (LWRP) via the sanitary sewer in accordance with established limits. This reagent feed system was installed to improve operational safety and process efficiency by eliminating the need for manual handling of various reagents used in the aqueous waste treatment processes. This was done by installing a delivery system that is controlled either remotely or locally via a programmable logic controller (PLC). The system consists of a pumping station, four sets of piping to each of six 6,800-L (1,800-gal) treatment tanks, air-actuated discharge valves at each tank, a pH/temperature probe at each tank, and the PLC-based control and monitoring system. During operation, the reagents are slowly added to the tanks in a preprogrammed and controlled manner while the pH, temperature, and liquid level are continuously monitored by the PLC. This paper presents the purpose of this reagent feed system, provides background related to LLNL`s low-level/mixed waste treatment processes, describes the major system components, outlines system operation, and discusses current status and plans.
Date: February 1, 1995
Creator: Dennison, D.K.; Bowers, J.S. & Reed, R.K.
Partner: UNT Libraries Government Documents Department

Lawrence Livermore National Laboratory Emergency Response Capability 2009 Baseline Needs Assessment Performance Assessment

Description: This document was prepared by John A. Sharry, LLNL Fire Marshal and Division Leader for Fire Protection and was reviewed by Sandia/CA Fire Marshal, Martin Gresho. This document is the second of a two-part analysis of Emergency Response Capabilities of Lawrence Livermore National Laboratory. The first part, 2009 Baseline Needs Assessment Requirements Document established the minimum performance criteria necessary to meet mandatory requirements. This second part analyses the performance of Lawrence Livermore Laboratory Emergency Management Department to the contents of the Requirements Document. The document was prepared based on an extensive review of information contained in the 2004 BNA, a review of Emergency Planning Hazards Assessments, a review of building construction, occupancy, fire protection features, dispatch records, LLNL alarm system records, fire department training records, and fire department policies and procedures. On October 1, 2007, LLNL contracted with the Alameda County Fire Department to provide emergency response services. The level of service called for in that contract is the same level of service as was provided by the LLNL Fire Department prior to that date. This Compliance Assessment will evaluate fire department services beginning October 1, 2008 as provided by the Alameda County Fire Department.
Date: December 30, 2009
Creator: Sharry, J A
Partner: UNT Libraries Government Documents Department