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Simple model for wind field computation from sparse data

Description: An initial attempt to carry out a simple numerical model that will interpolate and smooth the complete wind fields for an arbitrary planar region where only sparse wind data are available is summarized. The model contains four features: any arbitrary planar region with curved or straight line boundaries that do not cross themselves can be treated; the measured wind data can be irregularly distributed in the region; part of the code can be applied to any function that has two independent variables; and irrotational flow is assumed in smoothing the stream function. (ACR)
Date: January 1, 1980
Creator: Lee, W.H.
Partner: UNT Libraries Government Documents Department

Gyrokinetic approach in particle simulation

Description: A new scheme for particle simulation based on the gyrophase-averaged Vlasov equation has been developed. It is suitable for studying low-frequency microinstabilities and the associated anomalous transport in magnetically confined plasmas. The scheme retains the gyroradius effects but not the gyromotion; it is, therefore, far more efficient and versatile than the conventional ones. Furthermore, the reduced Vlasov equation is also amenable to analytical studies.
Date: October 1, 1981
Creator: Lee, W.W.
Partner: UNT Libraries Government Documents Department

Gyrokinetic particle simulation model

Description: A new type of particle simulation model based on the gyrophase-averaged Vlasov and Poisson equations is presented. The reduced system, in which particle gyrations are removed from the equations of motion while the finite Larmor radius effects are still preserved, is most suitable for studying low frequency microinstabilities in magnetized plasmas. It is feasible to simulate an elongated system (L/sub parallel/ >> L/sub perpendicular/) with a three-dimensional grid using the present model without resorting to the usual mode expansion technique, since there is essentially no restriction on the size of ..delta..x/sub parallel/ in a gyrokinetic plasma. The new approach also enables us to further separate the time and spatial scales of the simulation from those associated with global transport through the use of multiple spatial scale expansion. Thus, the model can be a very efficient tool for studying anomalous transport problems related to steady-state drift-wave turbulence in magnetic confinement devices. It can also be applied to other areas of plasma physics.
Date: July 1, 1986
Creator: Lee, W.W.
Partner: UNT Libraries Government Documents Department

Development of a high efficiency, automatic defrosting refrigerator/freezer. Phase I. Design and development. Volume 1. Executive summary. Final report

Description: Eighteen energy-saving design options were identified for the automatic defrost refrigerator/freezer unit. Projected energy savings and likely consumer acceptance of the design options were evaluated and seven promising options were selected for the development phase. Computer and laboratory studies of an improved condenser and evaporator design, new air flow path and fan housing design, improved defrost and refrigeration expansion valve control, and optimized cabinet insulation were performed. A prototype 16-cubic-foot automatic defrost refrigerator/freezer combining the seven energy saving design options was designed, built, and tested at Amana Refrigeraton, Inc. The Phase I prototype refrigerator/freezer had a 1.8 kWh per day energy consumption under the standard 900F closed door energy test. This is an energy factor of over 10 cubic feet per kWh per day and it represents better than a 50% improvement in unit efficiency over the most efficient unit presently available. A field test and market assessment (Phase II) is outlined. The test is designed to evaluate the unit performance in actual home use and marketability in a retail environment.
Date: February 1, 1980
Creator: Lee, W. D.
Partner: UNT Libraries Government Documents Department

UCB-NE-101 user's manual

Description: The purpose of this manual is to provide users of UCB-NE-101 with the information necessary to use UCB-NE-101 effectively. UCB-NE-101 calculates the concentration of solubility-limited species as a function of space and time and its mass flux rates from a waste sphere buried in a nuclear waste repository in water-saturated rock. The waste is surrounded by one type of rock, and some distance away, there is another type of rock. The inner layer of rock can be a backfill around a nuclear waste package and the outer layer the natural rock. The mass flux calculated is at the interface of the two layers. The species concentration calculated is in the inner layer. A constant concentration of the species, usually the solubility, is specified at the waste sphere/inner layer interface. Dissolution and transport is governed by the solubility of the species, and diffusion in the porous media. 1 ref., 1 fig.
Date: February 1, 1989
Creator: Lee, W.W.L.
Partner: UNT Libraries Government Documents Department

Molecular mechanisms of mutagenesis determined by the recombinant DNA technology

Description: A study of the alteration of the DNA in the mutant gene can determine mechanisms of mutation by distinguishing between mutations induced by transition, transversion, frameshifts of a single base and deletions involving many base pairs. The association of a specific pattern of response with a mutagen will permit detecting mutants induced by the mutagen with a reduced background by removing mutations induced by other mechanisms from the pool of potential mutants. From analyses of studies that have been conducted, it is quite apparent that there are substantial differences among mutagens in their modes of action. Of 31 x-ray induced mutants, 20 were large deletions while only 3 showed normal Southern blots. Only one mutant produced a sub-unit polypeptide of normal molecular weight and charge in the in vivo test whereas in vitro synthesis produced a second one. In contrast, nine of thirteen EMS induced mutants produced cross-reacting proteins with sub-unit polypeptide molecular weights equivalent to wild type. Two of three ENU induced mutants recently analyzed in our laboratory produced protein with sub-unit polypeptide molecular weight and electrical charge similar to the wild type stock in which the mutants were induced. One ENU induced mutation is a large deletion. 21 refs., 1 fig.
Date: January 1, 1985
Creator: Lee, W.R.
Partner: UNT Libraries Government Documents Department

RBE (relative biological effectiveness) of tritium beta radiation to gamma radiation and x-rays analyzed by both molecular and genetic methods

Description: The relative biological effectiveness (RBE) of tritium beta radiation to /sup 60/Co gamma radiation was determined using sex-linked recessive lethals (SLRL) induced in Drosophila melanogaster spermatozoa as the biological effect. The SLRL test, a measure of mutations induced in germ cells transmitted through successive generations, yields a linear dose-response curve in the range used in these experiments. From these ratios of the slopes of the /sup 3/H beta and the /sup 60/ Co gamma radiation linear dose response curves, an RBE of 2.7 is observed. When sources of error are considered, this observation suggests that the tritium beta particle is 2.7 /plus minus/ 0.3 times more effective per unit of energy absorbed in inducing gene mutations transmitted to successive generation than /sup 60/Co gamma radiation. Ion tracks with a high density of ions (high LET) are more efficient than tracks with a low ion density (low LET) in inducing transmissible mutations, suggesting interaction among products of ionization. Molecular analysis of x-ray induced mutations shows that most mutations are deletions ranging from a few base pairs as determined from sequence data to multi locus deletions as determined from complementation tests and Southern blots. 14 refs., 1 fig.
Date: January 1, 1988
Creator: Lee, W.R.
Partner: UNT Libraries Government Documents Department

A "Little Death": The Near-Death Experience and Tibetan Delogs

Description: Article exploring a phenomenon remarkably like the near-death experience that has been uncovered in Tibetan culture. Anthropologists have gathered accounts of contemporary and historical cases of remarkable people called delogs. Seemingly dead for several hours or days, these people revive spontaneously and tell detailed accounts of otherworldly journeys. These delogs are a bridge between contemporary near-death experiences and ancient shamanic practices.
Date: Spring 2001
Creator: Bailey, Lee W.
Partner: UNT Libraries

High explosive modeling in 2D Euler code for shaped charge problems

Description: The object of this study is to incorporate a programmed burn model of high explosive into a two-dimensional, smeared shock Eulerian hydrodynamic code. Huygen's principle and Chapman-Jouguet theory are used in defining the detonation velocity and the location where the high-explosive energy is released. Precalculated burn information such as burn times, burn distances, burn intervals, and burn fractions are implemented into the code before the hydrodynamic actions take place. Two shaped charge problems are tested using the present code and the results are compared with the experimental data, as well as those from other codes. 9 refs., 9 figs.
Date: January 1, 1986
Creator: Lee, W.H.
Partner: UNT Libraries Government Documents Department

FLUIDIZATION CHARACTERISTICS OF PARTICULATE FILTER MEDIA

Description: Predictions of water velocities at which fluidization and massive entrainment of filter media (sea sand, Ottawa sand, silica, and alumina) will occur in special filter beds are presented. Pressure gradients in the various fluidized beds and the maximum bed expansions expected are tabulated. (auth)
Date: June 12, 1958
Creator: Lee, W.J.
Partner: UNT Libraries Government Documents Department

Examination of four-sodium-water reaction target tubes

Description: Metallurgical examinations and evaluations were performed on a group of four target tubes from Atomic Power Development Associates (APDA) Rig 10. This group included two 2/sup 1///sub 4/ Cr--1 Mo ferritic steel tubes, one Type 304 SS, and one Incoloy 800 tube. These tubes had been exposed to small leaks of water in 600/sup 0/F sodium. Metallographic data indicate that the material loss (wastage) was primarily due to impact (or erosion) of liquid particles. No evidence of corrosion was found in the wasted areas of any target tubes. Minor corrosion was observed on the outside diameter of the austenitic stainless-steel tubes only in areas away from impact; no corrosion was detected on the outside diameter of the ferritic steel tubes. Hardness measurements and microstructural analyses revealed that the maximum temperature may have reached 1600/sup 0/F in the wasted areas. This localized temperature increase appeared to enhance the wastage process for all target tubes regardless of composition. Surface grain elongation and plastic deformation lines were observed in wasted areas, as well as in other areas. However, their cause(s) cannot be ascertained with respect to deformation due to water-jet impact, or deformation due to fabrication and handling, or both. Based on the volumetric measurements of the wastage zones produced, Incoloy 800 (tube No. 21) exhibited greater resistance to water-jet impact/erosion (penetration depth approximately 0.011 in. in 570 sec), while 2/sup 1///sub 4/ Cr--1 Mo ferritic steel displayed the least (depth of penetration 0.064 in. in 21 sec).
Date: June 26, 1970
Creator: Lee, W. T.
Partner: UNT Libraries Government Documents Department

UCB-NE-107 user's manual

Description: The purpose of this manual is to provide users of UCB-NE-107 with the information necessary to use UCB-NE-107 effectively. UCB-NE-107 is a computer code for calculating the fractional rate of readily soluble radionuclides that are released from nuclear waste emplaced in water-saturated porous media. Waste placed in such environments will gradually dissolve. For many species such as actinides and rare earths, the process of dissolution is governed by the exterior flow field, and the chemical reaction rate or leaching rate. However, for readily soluble species such as /sup 135/Cs, /sup 137/Cs, and /sup 129/I, it has been observed that their dissolution rates are rapid. UCB-NE-107 is a code for calculating the release rate at the waste/rock interface, to check compliance with the US Nuclear Regulatory Commission's (USNRC) subsystem performance objective. It is an implementation of the analytic solution given below. 5 refs., 2 figs.
Date: March 1, 1989
Creator: Lee, W.W.L.
Partner: UNT Libraries Government Documents Department

Computer simulations of anomalous transport

Description: Numerical plasma simulations have been carried out to study: (1) the turbulent spectrum and anomalous plasma transport associated with a steady state electrostatic drift turbulence; and (2) the anomalous energy transport of electrons due to shear-Alfven waves in a finite-..beta.. plasma. For the simulation of the steady state drift turbulence, it is observed that, in the absence of magnetic shear, the turbulence is quenched to a low level when the rotational transform is a rational number, while the turbulent level remains high for an irrational rotational transform.
Date: July 1, 1980
Creator: Lee, W.W. & Okuda, H.
Partner: UNT Libraries Government Documents Department

PIC method for modeling the shaped charge problems

Description: The PIC (particle-in-cell) method has been used for computing compressible, multimaterial problems for more than twenty years. The present work extends the same numerical approximation with operator splitting to hydroelastic-plastic flow problems in two-dimensional Eulerian coordinates. Applying the operator splitting method, the basic set of cylindrical equations is split in radial (r) and axial (z) directions. The calculations, performed in each direction separately, are alternated for each time advancement to maintain the accuracy of one-dimensional procedure. A shaped-charge problem is treated using the present code and the results are compared with the experimental data as well as those from other codes. 11 refs.
Date: January 1, 1986
Creator: Lee, W.H. & Kwak, D.
Partner: UNT Libraries Government Documents Department

Anomalous transport and stabilization of collisionless drift-wave instabilities

Description: Extensive numerical simulations have been carried out to study the enhanced transport processes associated with the collisionless drift wave instabilities. The results indicate that the shear is effective in reducing the anomalous particle diffusion as predicted by theory; however, it is less so for the accompanied electron heat transfer. The quasilinear decay of the density profile is found to be the dominant mechanism for the nonlinear saturation. (auth)
Date: December 1, 1975
Creator: Lee, W.W. & Okuda, H.
Partner: UNT Libraries Government Documents Department

Microstructure and properties of multiphase and functionally graded materials prepared by chemical vapor deposition

Description: The synthesis of multiphase and functionally graded materials by chemical vapor deposition is discussed from a perspective of controlling their composition and microstructure at a nano-scale level, and ultimately, tailoring their material properties. Prior research is briefly reviewed to address the current state of this novel material concept. Recent experimental results relating to controlling the selected properties of two multiphase systems, TiN + MoS{sub 2} and NiAl + Al{sub 2}O{sub 3}, are described to illustrate this concept`s potential merits and challenges for use in realistic applications.
Date: May 1, 1996
Creator: Lee, W.Y.
Partner: UNT Libraries Government Documents Department

A semi-Eulerian method for treating Lagrangian sliding interfaces

Description: In many two-dimensional Lagrangian radiation hydrodynamic calculations, shear along material boundaries is a serious problem. Since the mesh is tied to the material, this shear will cause distortions in the mesh that make the calculations very difficult. The approach described in this paper adopts a semi-Eulerian calculation that allows material flow through a Lagrangian mesh along an interface. The basic idea is to consider each point along the slip line temporarily as a double point. One would then calculate the motion of each point separately and then pull the points back together using the automatic rezone method. This would allow the materials to shear along the interface. This paper will describe the method as used in a two-dimensional Lagrangian code. The formation of a shaped charge jet is computed using the present method, and the results are discussed with and without the slip treatment.
Date: July 1, 1996
Creator: Lee, W.H.
Partner: UNT Libraries Government Documents Department

Waste package performance in unsaturated rock

Description: The unsaturated rock and near-atmospheric pressure of the potential nuclear waste repository at Yucca Mountain present new problems of predicting waste package performance. In this paper we present some illustrations of predictions of waste package performance and discuss important data needs. 11 refs., 9 figs., 1 tab.
Date: March 1, 1989
Creator: Pigford, T.H. & Lee, W.W.-L.
Partner: UNT Libraries Government Documents Department

Numerical simulation for two-phase jet problem

Description: A computer program TWOP was developed for obtaining the numerical solutions of three-dimensional, transient, two-phase flow system with nonequilibrium and nonhomogeneous conditions. TWOP employs two-fluid model and a set of the conservation equations formulated by Harlow and Amsden along with their Implicit Multi-Field (IMF) numerical technique that allows all degrees of couplings between the two fields. We have further extended the procedure of Harlow and Amsden by incorporating the implicit couplings of phase transition and interfacial heat transfer terms in the energy equations. Numerical results of two tested problems are presented to demonstrate the capabilities of the TWOP code. The first problem is the separation of vapor and liquid, showing that the code can handle the computational difficulties such as liquid packing and sharp interface phenomena. The second problem is the high pressure two-phase jet impinged on vertical plate, demonstrating the important role of the interfacial mass and momentum exchange.
Date: January 1, 1981
Creator: Lee, W.H. & Shah, V.L.
Partner: UNT Libraries Government Documents Department

Material void opening computation using particle method

Description: When performing the calculation of material flow in two dimensional Eulerian coordinates, one always encounters the difficulties of modeling the void opening due to material failure such as fracture, spallation, or phase change. The present studies use one type of particle to represent the material and another type for the void space. According to the flow conditions, the void space may grow with crack propagation or may be recombined with the void space closed up when the volume decreases. The penetration of a copper rod into, and eventually through a steel plate, is calculated using the present code.
Date: January 1, 1988
Creator: Lee, W.H. & Painter, J.W.
Partner: UNT Libraries Government Documents Department