Accurate and efficient simulation of chemical transport processes in the unsaturated zone of Yucca Mountain is important to evaluate the performance of the potential repository. The scale of the unsaturated zone model domain for Yucca Mountain (50 km{sup 2} area with a 600 meter depth to the water table) requires a large gridblock approach to efficiently analyze complex flow & transport processes. The conventional schemes based on finite element or finite difference methods perform well for dispersion-dominated transport, but are subject to considerable numerical dilution/dispersion for advection-dominated transport, especially when a large gridblock size is used. Numerical dispersion is an artificial, grid-dependent chemical spreading, especially for otherwise steep concentration fronts. One effective scheme to deal with numerical dispersion is the random walk particle method (RWPM). While significant progress has been made in developing RWPM algorithms and codes for single continuum systems, a random walk particle tracker, which can handle chemical transport in dual-continua (fractured porous media) associated with irregular grid systems, is still absent (to our knowledge) in the public domain. This is largely due to the lacking of rigorous schemes to deal with particle transfer between the continua, and efficient schemes to track particles in irregular grid systems. The …

{l_brace}311{r_brace} defects and dislocation loops are formed after ion-implantation and annealing of a silicon wafer. Recent Transmission Electron Microscopy studies by Li and Jones have shown that sub-threshold dislocation loops nucleate from {l_brace}311{r_brace} defects. In our study, the conjugate gradient method with the Stillinger Weber potential is used to relax different configurations such as {l_brace}311{r_brace} defects with a maximum of five chains and perfect dislocation loops. From the formation energies thus obtained we find that there is an optimal width for each length of the {l_brace}311{r_brace} defects. Moreover the relative stability of {l_brace}311{r_brace}s and loops is studied as a function of defect size. We observe that at very small sizes the perfect loops are more stable than the {l_brace}311{r_brace}s. This may provide an explanation for the experimental observation by Robertson et al that, in an annealing study of end of range damage of amorphized samples, 45% of the loops had nucleated in the first 10 minutes of anneal. We propose that homogeneous nucleation, as against unfaulting of the {l_brace}311{r_brace}s, could be the source of these loops.

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This paper presents our early results in applying data mining techniques to the problem of finding radio-emitting galaxies with a bent-double morphology. In the past, astronomers on the FIRST (Faint Images of the Radio Sky at Twenty-cm) survey have detected such galaxies by first inspecting the radio images visually to identify probable bent-doubles, and then conducting observations to confirm that the galaxy is indeed a bent-double. Our goal is to replace this visual inspection by a semi-automated approach. In this paper, we present a brief overview of data mining, describe the features we use to discriminate bent-doubles from non-bent-doubles, and discuss the challenges faced in defining meaningful features in a robust manner. Our experiments show that data mining, using decision trees, can indeed be a viable alternative to the visual identification of bent-double galaxies.

A number of tools and equipment pieces are required to facilitate planned test operations during Phases 3 and 4 of the Phased Startup Initiative (PSI). These items will be used in assessing residual canister sludge quantities on cleaned fuel assemblies, sorting coarse and fine scrap fuel pieces, assessing the size distribution of scrap pieces, loading scrap into a canister, and measuring the depth of the accumulated scrap in a canister. This work plan supercedes those previously issued for development of several of these test items. These items will be considered prototype equipment until testing has confirmed their suitability for use in K West Basin. The process described in AP-EN-6-032 will be used to qualify the equipment for facility use. These items are considered non-OCRWM for PSI Phase 3 applications. The safety classification of this equipment is General Service, with Quality Level 0 (for PSI Phase 3). Quality Control inspections shall be performed to verify basic dimensions and overall configurations of fabricated components, and any special quality control verifications specified in this work plan (Section 3.1.5). These inspections shall serve to approve the test equipment for use in K West Basin (Acceptance Tag). This equipment is for information gathering only during …

In 1999, Engineering at Lawrence Livermore National Laboratory faced competing priorities to meet critical project milestones, insistent pressures to restructure internally to promote long-term technological growth, and immediate demands to reassign employees as major projects terminated and new ones emerged. This drive for change occurred among an unprecedented level of turmoil within the nuclear weapons design and manufacturing community. I believe the technical problems were more demanding this year and the environment within which they were accomplished more challenging, pushing us to accomplish more during greater turbulence than any other time in my tenure here. I am pleased to report that we met many key milestones and achieved numerous technological breakthroughs. In the project support areas, demands presented by our customers shifted significantly over the year. In the lasers area, we continued the detailed designs for the over $1 billion National Ignition Facility (NIF) super laser, paving the way for the procurement of components and structures for what is probably the largest high-tech construction project in the world. This work was undertaken in an environment of significant management and structural changes, with increased reporting requirements from the Department of Energy, starting in the middle of 1999. Despite these changes, our …

The Fuel Retrieval Subproject was established as part of the Spent Nuclear Fuel Project (SNF Project) to retrieve and repackage the SNF located in the K Basins. The Fuel Retrieval System (FRS) construction work is complete in the KW Basin, and start-up testing is underway. Design modifications and construction planning are also underway for the KE Basin. An independent review of the design verification process as applied to the K Basin projects was initiated in support of preparation for the SNF Project operational readiness review (ORR). A Design Verification Status Questionnaire, Table 1, is included which addresses Corrective Action SNF-EG-MA-EG-20000060, Item No.9 (Miller 2000).

The pressure retaining capability of the PUREX process connector is documented. A context is provided for the connector's current use within existing Projects. Previous testing and structural analyses campaigns are outlined. The deficient condition of the current inventory of connectors and assembly wrenches is highlighted. A brief history of the connector is provided. A bibliography of pertinent references is included.

A common problem in signal processing is to estimate the structure of an object from noisy measurements linearly related to the desired image. These problems are broadly known as inverse problems. A key feature which complicates the solution to such problems is their ill-posedness. That is, small perturbations in the data arising e.g. from noise can and do lead to severe, non-physical artifacts in the recovered image. The process of stabilizing these problems is known as regularization of which Tikhonov regularization is one of the most common. While this approach leads to a simple linear least squares problem to solve for generating the reconstruction, it has the unfortunate side effect of producing smooth images thereby obscuring important features such as edges. Therefore, over the past decade there has been much work in the development of edge-preserving regularizers. This technique leads to image estimates in which the important features are retained, but computationally the y require the solution of a nonlinear least squares problem, a daunting task in many practical multi-dimensional applications. In this thesis we explore low-order models for reducing the complexity of the re-construction process. Specifically, B-Splines are used to approximate the object. If a ''proper'' collection B-Splines are …

Aggregates in thin films of conjugated polymers form excimer states and significantly reduce the photo- and electroluminescence efficiency in devices produced from these materials. We have studied the aggregate formation in thin films of MEH-PPV by near-field scanning optical microscopy and spectroscopy. Local photoluminescence spectroscopy and photo-bleaching experiments have been used to show that thin films of MEH-PPV are homogeneously aggregated and do not form aggregated domains.

The Lawrence Livermore National Laboratory (LLNL) was founded in 1952 and has been managed since its inception by the University of California (UC) for the U.S. Department of Energy (DOE). Because of this long association with UC, the Laboratory has been able to recruit a world-class workforce, establish an atmosphere of intellectual freedom and innovation, and achieve recognition in relevant fields of knowledge as a scientific and technological leader. This environment and reputation are essential for sustained scientific and technical excellence. As a DOE national laboratory with about 7,000 employees, LLNL has an essential and compelling primary mission to ensure that the nation's nuclear weapons remain safe, secure, and reliable and to prevent the spread and use of nuclear weapons worldwide. The Laboratory receives funding from the DOE Assistant Secretary for Defense Programs, whose focus is stewardship of our nuclear weapons stockpile. Funding is also provided by the Deputy Administrator for Defense Nuclear Nonproliferation, many Department of Defense sponsors, other federal agencies, and the private sector. As a multidisciplinary laboratory, LLNL has applied its considerable skills in high-performance computing, advanced engineering, and the management of large research and development projects to become the science and technology leader in those areas …

Hanford Site Groundwater Monitoring: Setting, Sources, and Methods

In order to reduce high radiation dose rates encountered when core sampling some radioactive waste tanks the addition of 240 lbs. of lead shielding is being considered to the shielded receiver tube on core sample trucks No.1, No.3 and No.4. The lead shielding is 4 inch diameter x 1/2 inch thick half rounds that have been installed around the SR tube over its' full length. Using three unreleased but independently reviewed structural analyses HNF-6018 justifies the addition of the lead shielding.

This fact sheet contains a description of South Dakota's wind energy resources, and the state's financial incentives that support the installation of renewable energy systems. The fact sheet includes a list of contacts for those interested in obtaining more information.

Data sets that are being produced by today's simulations, such as the ones generated by DOE's ASCI program, are too large for real-time exploration and visualization. Therefore, new methods of visualizing these data sets need to be investigated. The authors present a method that combines isosurface representations of different resolutions into a seamless solution, virtually free of cracks and overlaps. The solution combines existing isosurface generation algorithms and wavelet theory to produce a real-time solution to multiple-resolution isosurfaces.

This study of adhesional strength and surface analysis of encapsulant and silicon cell samples from a Natural Bridges National Monument (NBNM) Spectrolab module is an attempt to understand from its success. The module was fabricated using polyvinyl butyral (PVB) as an encapsulant. The average adhesional shear strength of the encapsulant at the cell/encapsulant interface in this module was 4.51 MPa or {approximately} 18% lower than that in currently manufactured modules. Typical encapsulant surface composition was as follows: C 75.0 at.% O 23.2 at.%, and Si 1.6 at.%, with Ag {approximately}0.2 at.% and Pb {approximately} 0.5 at.% with some tin respectively over the grid lines and solder bond. Representative silicon cell surface composition was: K 1.4 at.%, C 20.8 at.%, Sn 0.94 at.%, O 15.1 at.%, Na 2.7 at.% and Si 59.0 at.%. The presence of tin detected on the silicon cell surface may be attributed to corrosion of solder bond. The module differs from typical contemporary modules in the use of PVB, metallic mesh type interconnection, and silicon oxide AR coating.

The newly revised standard, IEEE Std 929-2000, has significant positive implications for those designing inverters for utility-interconnected PV systems and for designers and installers of such systems. A working group of roughly 20 people, including PV systems designers/installers, PV inverter manufacturers and utility engineers spent close to 3 years developing a standard that would be useful and beneficial to all.

Wind resources in the state of Iowa show great potential for wind energy development. This fact sheet provides a brief description of the state's wind resources and the financial incentives available for the development of wind energy systems. It also provides a list of contacts for more information.

Wind resources in the state of Kansas show great potential for wind energy development according to the wind resource assessment conducted by the Kansas Electric Utilities Research Program, UWIG, and DOE. This fact sheet provides a brief description of the resource assessment and description of the state's new educational wind kiosk as well as its green power program and financial incentives available for the development of renewable energy technologies. A list of contacts for more information is also included.

The authors discuss transverse polarization distribution and fragmentation functions, in particular, T-odd functions with transverse momentum dependence, which might be relevant for the description of single transverse spin asymmetries. The role of intrinsic transverse momentum in the expansion in inverse powers of the hard scale is elaborated upon. The sin {phi} single spin asymmetry in the process e {rvec p} {r_arrow} e{prime} {pi}{sup +} X as recently reported by the HERMES Collaboration is investigated, in particular, by using the bag model.

This paper describes an approach that was developed to produce structured models that graphically reflect the requirements contained within a text document. The document used in this research is a draft policy document governing business in a research and development environment. In this paper, the authors present a basic understanding of why this approach is needed, the techniques developed, lessons learned during modeling and analysis, and recommendations for future investigation. The modeling method applied on the policy document was developed as an extension to entity relationship (ER) diagrams, which built in some structural information typically associated with object-oriented techniques. This approach afforded some structure as an analysis tool, while remaining flexible enough to be used with the text document. It provided a visual representation that allowed further analysis and layering of the model to be done.

Natural, renewable resources such as vegetable oils and recycled restaurant greases can be chemically transformed into clean-burning biodiesel fuels. As its name implies, biodiesel is like diesel fuel except that it's organically produced. It's also safe for the environment, biodegradable, and produces significantly less air pollution than diesel fuel.

The authors define what they mean by a 30-year module life and the testing protocol that they believe is involved in achieving such a prediction. However, they do not believe that a universal test (or series of tests) will allow for such a prediction to be made. They can test for a lot of things, but they believe it is impossible to provide a 30-year certification for any PV module submitted for test. They explain their belief in this paper.

This report is the first revision to ``Radiological Performance Assessment for the E-Area Vaults Disposal Facility, Revision 0'', which was issued in April 1994 and received conditional DOE approval in September 1994. The title of this report has been changed to conform to the current name of the facility. The revision incorporates improved groundwater modeling methodology, which includes a large data base of site specific geotechnical data, and special Analyses on disposal of cement-based wasteforms and naval wastes, issued after publication of Revision 0.