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The goal of the data intensive LDRD was to investigate the fundamental research issues underlying the application of High Performance Computing (HPC) resources to the challenges of data intensive computing. We explored these issues through four targeted case studies derived from growing LLNL programs: high speed text processing, massive semantic graph analysis, streaming image feature extraction, and processing of streaming sensor data. The ultimate goal of this analysis was to provide scalable data management algorithms to support the development of a predictive knowledge capability consistent with the direction of Aurora.

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I study the quantum mechanics of a spin interacting with an environment. Although the evolution of the whole system is unitary, the spin evolution is not. The system is chosen so that the spin exhibits loss of quantum coherence, or wavefunction collapse,'' of the sort usually associated with a quantum measurement. The system is analyzed from the point of view of the spin density matrix (or Schmidt path''), and also using the consistent histories (or decoherence functional) approach.

I study the quantum mechanics of a spin interacting with an environment. Although the evolution of the whole system is unitary, the spin evolution is not. The system is chosen so that the spin exhibits loss of quantum coherence, or ``wavefunction collapse,`` of the sort usually associated with a quantum measurement. The system is analyzed from the point of view of the spin density matrix (or ``Schmidt path``), and also using the consistent histories (or decoherence functional) approach.

The purpose of the Workshop 'Excellence Empowered by a Diverse Academic Workforce: Achieving Racial & Ethnic Equity in Chemistry' was to promote the development of a cadre of academic leaders who create, implement and promote programs and strategies for increasing the number of racial and ethnic minorities to equitable proportions on the faculties of departments throughout the academic chemistry community. An important objective of the workshop was to assist in creating an informed and committed community of chemistry leaders who will create, implement and promote programs and strategies to advance racial and ethnic equity in both the faculty and the student body with the goal of increasing the number of U.S. citizen underrepresented minorities (URM) participating in academic chemistry at all levels, with particular focus on the pipeline to chemistry faculty. This objective was met by (1) presentations of detailed data describing current levels of racial and ethnic minorities on the faculties of chemistry departments; (2) frank discussion of the obstacles to and benefits of racial/ethnic diversity in the chemistry professoriate; (3) summary of possible effective interventions and actions; and (4) promotion of the dissemination and adoption of initiatives designed to achieve racial/ethnic equity. Federal programs over the past thirty …

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Risk assessment techniques vary from purely qualitative approaches, through a regime of semi-qualitative to the more traditional quantitative. Constraints such as time, money, manpower, skills, management perceptions, risk result communication to the public, and political pressures all affect the manner in which risk assessments are carried out. This paper surveys some risk matrix techniques, examining the uses and applicability for each. Limitations and problems for each technique are presented and compared to the others. Risk matrix approaches vary from purely qualitative axis descriptions of accident frequency vs consequences, to fully quantitative axis definitions using multi-attribute utility theory to equate different types of risk from the same operation.

At the Lawrence Livermore National Laboratory, we have prepared a Safety Analysis Report for the Department of Energy on our Building 332 Plutonium Handling Facility. This SAR includes an analysis of potential accident scenarios which could lead to offsite consequences to the public having not only radiological exposures, but also exposures to toxic gases such as chlorine. This paper presents a risk analysis of pressurized chlorine gas system proposed for use at Building 332. The focus of the analysis is to calculate the predicted frequency of an unmitigated leak of chlorine from the system which could result in the dispersal of the entire contents of the gas cylinder to the environment. Modeled are postulated valve leaks or pipe ruptures occurring anywhere in the distribution system, as well as the potential failure of leak mitigation. The fundamental credibility of this type of accident is established. The importance of a reliable leak mitigation system is demonstrated, and the dependence of the results on less than optimal data is discussed in the context of uncertainty and sensitivity analyses.

A large portion of the slug failures which occurred during 1955 were of the ``hot-spot`` type. Observation of these failures has shown them to be the result of intergranular corrosion attack of the aluminum jacket. Intergranular corrosion is presently considered to occur in water temperature above 150 C; a flow disturbance which causes non-uniform coolant temperatures is suspected as the cause of failure.The present of a cocked slug, or a bowed slug column, might provide this flow disturbance. 189-D laboratory tests have shown that flow seating the slug charge allows slugs to cock in the tube. It has also been found that these cocked slugs may be lifted to close proximity of the tube wall by the axial load on the slug column due to process water flow. It is believed that in cases such as this, slug and coolant temperatures may become critical. Present charging procedures allow for flow seating of the slug column. The distance the column is flow seated varied from very little to 3 or 4 inches depending on the particular charge. It is believed that this practice can lead to the situation observed in the laboratory tests. During the past two months, there has been …

High-pressure freezing is the preferred method to prepare thick biological specimens for ultrastructural studies. However, the advantages obtained by this method often prove unattainable for samples that are difficult to handle during the freezing and substitution protocols. Delicate and sparse samples are difficult to manipulate and maintain intact throughout the sequence of freezing, infiltration, embedding, and final orientation for sectioning and subsequent TEM imaging. An established approach to surmount these difficulties is the use of cellulose microdialysis tubing to transport the sample. With an inner diameter of 200 micrometers, the tubing protects small and fragile samples within the thickness constraints of high-pressure freezing, and the tube ends can be sealed to avoid loss of sample. Importantly, the transparency of the tubing allows optical study of the specimen at different steps in the process. Here, we describe the use of a micromanipulator and microinjection apparatus to handle and position delicate specimens within the tubing. We report two biologically significant examples that benefit from this approach, 3D cultures of mammary epithelial cells and cochlear outer hair cells. We illustrate the potential for correlative light and electron microscopy as well as electron tomography.

Theoretical studies of electron interactions in two families of novel materials were conducted. The temperature-concentration phase diagram of doped bismuthate superconductors was described using a coarse grained anisotropic Heisenberg model. A simplified model of electron interactions on buckminsterfullerene was studied. A simple model for electron-vibron interactions on charged buckminsterfullerene C{sub 60}{sup n {minus}}, was solved at both weak and strong couplings.

Crystalline Silicotitanate (CST) was selected as one of the alternatives to the In-Tank Precipitation Process (ITP) for removal of cesium from the salt waste at Savannah River Site. The proposed salt waste treatment process using CST would involve passing a filtered salt waste through a fixed bed of CST. The CST would remove the cesium from the salt waste by ion exchange and the decontaminated salt would be incorporated into the Saltstone Process. This report documents the results of investigations into the mixing and re-suspension characteristics of two 10 wt percent CST slurries.

Three candidate antifoam/defoam agents were tested on a laboratory scale with simulated KTPB slurry using the proposed STTPB process precipitation, concentration, and washing steps. Conclusions are if air entrainment in the slurry is carefully avoided, little or no foam will be generated during normal operations during precipitation, concentration, and washing of the precipitate. Three candidate antifoam/defoam agents were tested on a laboratory scale with simulated KTPB slurry using the proposed STTPB process precipitation, concentration and washing steps. In all cases little or no foam formed during normal operations of precipitation, concentration and washing. Foam was produced by purposely-introducing gas sub-surface into the slurry. Once produced, the IIT B52 antifoam was effective in defoaming the slurry. In separate foam column tests, all antifoam/defoam agents were effective in mitigating foam formation and in defoaming a foamed 10 wt % insoluble solids slurry. Based on the results in this report as well as foam column studies at IIT, it is recommended that IIT B52 antifoam at the 1000 ppmV level be used in subsequent STTPB work where foaming is a concern. This study indicates that the addition of antifoam agent hinders the recovery of NaTPB during washing. Washing precipitate with no antifoam agent …

At the end of 1992, the PUREX and UO{sub 3} plants were deemed no longer necessary for the defense needs of the United States. Although no longer necessary, they were very costly to maintain in their post-operation state. The DOE embarked on a deactivation strategy for these plants to reduce the costs of providing continuous surveillance of the facilities and their hazards. Deactivation of the PUREX and UO{sub 3} plants was estimated to take 5 years and cost $222.5 million and result in an annual surveillance and maintenance cost of $2 million. Deactivation of the PUREX/UO{sub 3} plants officially began on October 1, 1993. The deactivation was 15 months ahead of the original schedule and $75 million under the original cost estimate. The annual cost of surveillance and maintenance of the plants was reduced to less than $1 million.

The goal of this project is to measure transport through CNTs and study effects of confinement at molecular scale. This work is motivated by several simulation papers in high profile journals that predict significantly higher transport rates of gases and liquids through carbon nanotubes as compared with similarly-sized nanomaterials (e.g. zeolites). The predictions are based on the effects of confinement, atomically smooth pore walls and high pore density. Our work will provide the first measurements that would compare to and hopefully validate the simulations. Gas flux is predicted to be >1000X greater for SWNTs versus zeolitesi. A high flux of 6-30 H2O/NT/ns {approx} 8-40 L/min for a 1cm{sup 2} membrane is also predicted. Neutron diffraction measurements indicate existence of a 1D water chain within a cylindrical ice sheet inside carbon nanotubes, which is consistent with the predictions of the simulation. The enabling experimental platform that we are developing is a semipermeable membrane made out of vertically aligned carbon nanotubes with gaps between nanotubes filled so that the transport occurs through the nanotubes. The major challenges of this project included: (1) Growth of CNTs in the suitable vertically aligned configuration, especially the single wall carbon nanotubes; (2) Development of a process …

A numerical method is described for inviscid, compressible, multi-material flow in two space dimensions. The flow is governed by the multi-material Euler equations with a general mixture equation of state. Composite overlapping grids are used to handle complex flow geometry and block-structured adaptive mesh refinement (AMR) is used to locally increase grid resolution near shocks and material interfaces. The discretization of the governing equations is based on a high-resolution Godunov method, but includes an energy correction designed to suppress numerical errors that develop near a material interface for standard, conservative shock-capturing schemes. The energy correction is constructed based on a uniform pressure-velocity flow and is significant only near the captured interface. A variety of two-material flows are presented to verify the accuracy of the numerical approach and to illustrate its use. These flows assume an equation of state for the mixture based on Jones-Wilkins-Lee (JWL) forms for the components. This equation of state includes a mixture of ideal gases as a special case. Flow problems considered include unsteady one-dimensional shock-interface collision, steady interaction of an planar interface and an oblique shock, planar shock interaction with a collection of gas-filled cylindrical inhomogeneities, and the impulsive motion of the two-component mixture in …

This waste analysis plan (WAP) has been prepared for the Low-Level Burial Grounds that are located in the 200 East and 200 West Areas of the Hanford Facility, Richland, Washington. This WAP documents the methods used to characterize and obtain and analyze representative samples of waste managed at this unit.

Work performed as a part of this ER sets the foundation for applications of high brightness light sources to important homeland security and nonproliferation problems. Extensive modeling has been performed with the aim to understand the performance of a class of interrogation systems that exploit nuclear resonance fluorescence to detect specific isotopes, of particular importance for national security and industry.

The calculation of downwind concentrations from non-traditional sources, such as explosions, provides unique challenges to dispersion models. The US Department of Energy has assigned the Atmospheric Release Advisory Capability (ARAC) at the Lawrence Livermore National Laboratory (LLNL) the task of estimating the impact of accidental radiological releases to the atmosphere anywhere in the world. Our experience includes responses to over 25 incidents in the past 16 years, and about 150 exercises a year. Examples of responses to explosive accidents include the 1980 Titan 2 missile fuel explosion near Damascus, Arkansas and the hydrogen gas explosion in the 1986 Chernobyl nuclear power plant accident. Based on judgment and experience, we frequently estimate the source geometry and the amount of toxic material aerosolized as well as its particle size distribution. To expedite our real-time response, we developed some automated algorithms and default assumptions about several potential sources. It is useful to know how well these algorithms perform against real-world measurements and how sensitive our dispersion model is to the potential range of input values. In this paper we present the algorithms we use to simulate explosive events, compare these methods with limited field data measurements, and analyze their sensitivity to input parameters. …

The authors are in the re-evaluating of all the actinide cross section evaluations in LLNL's ENDL database, starting with uranium and focusing on inventory changing reactions. This article describes their first serious pass at updating the uranium cross section data, including estimates of cross section uncertainties. Furthermore, they are developing new tools to automate the re-evaluation and this article contains some preliminary results from these codes, namely the {sup 235}U(n, 2n) and {sup 238}U(n, 2n) evaluations.

A novel model has been developed to capture size scale and gradient effects within the context of continuum crystal plasticity by explicitly incorporating details of dislocation transport, coupling dislocation transport to slip, evolving spatial distributions of dislocations consistent with the flux, and capturing the interactions among various dislocation populations. Dislocation flux and density are treated as nodal degrees of freedom in the finite element model, and they are determined as part of the global system of equations. The creation, annihilation and flux of dislocations between elements are related by transport equations. Crystallographic slip is coupled to the dislocation flux and the stress state. The resultant gradients in dislocation density and local lattice rotations are analyzed for geometrically necessary and statistically stored dislocation contents that contribute to strength and hardening. Grain boundaries are treated as surfaces where dislocation flux is restricted depending on the relative orientations of the neighboring grains. Numerical results show different behavior near free surfaces and non-deforming surfaces resulting from differing levels of dislocation transmission. Simulations also show development of dislocation pile-ups at grain boundaries and an increase in flow strength reminiscent of the Hall-Petch model. The dislocation patterns have a characteristic size independent of the numerical discretization.

Argonne's mission is to serve DOE and national security by advancing the frontiers of knowledge, by creating and operating forefront scientific user facilities, and by providing innovative and effective approaches and solutions to energy, environmental, and security challenges to national and global well-being, in the near and long term, as a contributing member of the DOE laboratory system. We contribute significantly to DOE's mission in science, energy resources, environmental stewardship, and national security, with lead roles in the areas of science, operation of scientific facilities, and energy. In accomplishing our mission, we partner with DOE, other federal laboratories and agencies, the academic community, and the private sector. Argonne is pursuing ten visionary strategic goals to deliver extraordinary science and technology with significant value to the nation: (1) Develop the technologies and infrastructure needed to produce, store, and distribute hydrogen fuel. (2) Close the nuclear fuel cycle, reducing the cost of nuclear waste disposal by billions of dollars and disposing of weapons-grade plutonium and actinides. (3) Develop advanced nuclear power technologies that are safe, economical, proliferation-resistant, and environmentally sustainable. (4) Plan, design, construct, and operate the Rare Isotope Accelerator (RIA) and make fundamental discoveries in nuclear physics and astrophysics. (5) Construct …