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CALOR as a Single Code Including a Modular Version of HETC
No full textThe major components of CALOR are HETC, MORSE, EGS4, EGS4PREP, and SPECT, working sequentially on calorimeter detector for high energy physics, experimental analysis, or shielding studies. An effort to combine the components into a single code is described. The new code is modular in nature. For example, one may run only HETC and MORSE. In addition, HETC itself has become modular and may be run in three energy options--up to 2.5 GeV, 15 GeV, and 20 TeV. The size of the low-energy option of HETC is less than 40% of the original HETC. A great advantage of the new code is the elimination of three huge files for passing information from one component to another
Construction of Difference Equations Using Lie Groups
No full textThe theory of prolongations of the generators of groups of point transformations to the grid point values of dependent variables and grid spacings is developed and applied to the construction of group invariant numerical algorithms. The concepts of invariant difference operators and generalized discrete sources are introduced for the discretization of systems of inhomogeneous differential equations and shown to produce exact difference equations. Invariant numerical flux functions are constructed from the general solutions of first order partial differential equations that come out of the evaluation of the Lie derivatives of conservation forms of difference schemes. It is demonstrated that invariant numerical flux functions with invariant flux or slope limiters can be determined to yield high resolution difference schemes. The introduction of an invariant flux or slope limiter can be done so as not to break the symmetry properties of a numerical flux-function
Maximum-Path Leaves Relative to Vertices and the Vertex One Center of a Spanning Tree: An Enumeration and Analysis of Configurations
No full textThis paper enumerates the configurations of a pair of vertices (one of which is a leaf) relative to the unique vertex one center and the leaf of greatest path length from this center in a spanning tree of a graph. From this enumeration, it demonstrates that the vertex one center is between the vertex and the leaf of greatest path length from the vertex for every such pair of vertices. Using this result this paper develops an algorithm for the optimal reconfiguration of a tree infrastructure required to recover from the failure of a network element
Engineering Development of Slurry Bubble Column Reactor (SBCR) Technology
No full textThe major technical objectives of this program are threefold: (1) to develop the design tools and a fundamental understanding of the fluid dynamics of a slurry bubble column reactor to maximize reactor productivity, (2) to develop the mathematical reactor design models and gain an understanding of the hydrodynamic fundamentals under industrially relevant process conditions, and (3) to develop an understanding of the hydrodynamics and their interaction with the chemistries occurring in the bubble column reactor. Successful completion of these objectives will permit more efficient usage of the reactor column and tighter design criteria, increase overall reactor efficiency, and ensure a design that leads to stable reactor behavior when scaling up to large diameter reactors
Enhanced Electron Attachment to Highly-Excited States of Molecules: Implications for Plasma Processing Discharges
No full textRecent studies show that large negative ion densities exist in plasma processing discharges, including those of weakly electronegative gases such as SiH{sub 4} and CF{sub 4}. Also, there is strong evidence that the negative ions could be the precursors for particulate formation in processing discharges. Even though it is now well established that large concentrations of negative ions exist in processing discharges, and that they play a crucial role in such discharges, the source of such high negative ion densities has not been clarified. In particular, gases like SiH{sub 4} and CH{sub 4}, which are commonly used in processing discharges, attach electrons only weakly in their ground electronic states (see the references). Due to the lack of an alternative mechanism, the origin of large negative ion densities in such weakly electronegative gases has been frequently attributed to electron attachment to radicals (molecular fragments) or other byproducts produced in the discharge. This hypothesis had not been tested in direct electron attachment measurements
High Explosive Radio Telemetry System
No full textThis paper overviews the High Explosive Radio Telemetry (HERT) system, under co-development by Los Alamos National Laboratories and Allied Signal Federal Manufacturing & Technologies. This telemetry system is designed to measure the initial performance of an explosive package under flight environment conditions, transmitting data from up to 64 sensors. It features high speed, accurate time resolution (10 ns) and has the ability to complete transmission of data before the system is destroyed by the explosion. In order to affect the resources and performance of a flight delivery vehicle as little as possible, the system is designed such that physical size, power requirements, and antenna demands are as small as possible
Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures
No full textThis project attempts to demonstrate the effectivensss of exploiting thin-layered, low energy deposits at the distal margin of a propagating turbinite complex through u se of hydraulically fractgured horizontal of high-angle wells. TGhe combinaton of a horizontal or high-angle weoo and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore
A New Simplified System for the Evaluation of BNCT Pharmaceuticals
No full textA system for testing potential BNCT pharmaceuticals in cell cultures has been developed with the cooperation of Oak Ridge National Laboratory (ORNL), the University of Tennessee Chemistry Department and the University of Tennessee Nuclear Engineering Department. A BNCT test model has been established with the use of the human lung cancer cell line A 549. These cells were maintained in standard laboratory facilities and subjected to boronated chemicals. Following toxicity studies the human luug cancer cells were exposed to {sup 252}Cf neutron sources provided by the Radiochemical Engineering Development Center (REDC) at ORNL The isotope {sup 252}Cf performs effectively for BNCT applications. The neutron spectrum is similar to that of a reactor fission source with an average energy of 2.1 MeV. A 50 mg source of {sup 252}Cf moderated by water provides a source on the order of 1 x 10{sup 9} thermal neutrons/cm{sup 2}/sec at a distance of 3 cm. The half-life of {sup 252}Cf is 2.65 years, and thus may provide a simple and reliable source of neutrons for BNCT in locations without suitable nuclear reactors. The REDC of ORNL stores and processes the U.S. stockpile of {sup 252}Cf
Development of an Immersive Environment to Aid in Automatic Mesh Generation LDRD Final Report
No full textThe purpose of this work was to explore the use of immersive technologies, such as those used in synthetic environments (commordy referred to as virtual realily, or VR), in enhancing the mesh- generation process for 3-dimensional (3D) engineering models. This work was motivated by the fact that automatic mesh generation systems are still imperfect - meshing algorithms, particularly in 3D, are sometimes unable to construct a mesh to completion, or they may produce anomalies or undesirable complexities in the resulting mesh. It is important that analysts and meshing code developers be able to study their meshes effectively in order to understand the topology and qualily of their meshes. We have implemented prototype capabilities that enable such exploration of meshes in a highly visual and intuitive manner. Since many applications are making use of increasingly large meshes, we have also investigated approaches to handle large meshes while maintaining interactive response. Ideally, it would also be possible to interact with the meshing process, allowing interactive feedback which corrects problems and/or somehow enables proper completion of the meshing process. We have implemented some functionality towards this end -- in doing so, we have explored software architectures that support such an interactive meshing process. This work has incorporated existing technologies developed at SandiaNational Laboratories, including the CUBIT mesh generation system, and the EIGEN/VR (previously known as MUSE) and FLIGHT systems, which allow applications to make use of immersive technologies and advanced human computer interfaces.
Geologic map of the Mine Mountain area, Nevada Test Site, southern Nevada
No full textThe Mine Mountain area is a small range of hills on the west side of the central Yucca Flat basin on the Nevada Test Site, Nye County, Nevada. This map portrays the very complex relationships among the pre-Tertiary stratigraphic units of the region. Rocks and structures of the Mine Mountain area record the compounded effects of: (1) eastward-directed, foreland-vergent thrusting; (2) younger folds and thrusts formed by hinterland vergence in a general westerly direction; and (3) low-angle normal faulting formed by extension along a northeast-southwest trend. All of these structures are older than the oldest middle Miocene volcanic rocks that were deposited on the flanks of the Mine Mountain terrane. High-angle faults that post-date these volcanic rocks locally show displacements of several hundred meters, but do not strongly affect patterns in the pre-Tertiary rocks