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University of California, Los Angeles Campus School of Medicine Atomic Energy Project quarterly progress report for period ending March 31, 1952

Description: The fifteenth quarterly report being submitted for Contract No. AT04-1-GEN-12 is issued in accordance with Service Request Number 1 except for the report of the Alamogordo Section, Code 91810, which is submitted in accordance with the provisions of Service Request Number 2. Work is in progress on continuing existing projects. In addition, new projects have been initiated including the Kinetics and Mechanism of Protein Denaturation (10018); The Effect of Irradiation on the Constituents of Embryonic Serum (30033); and The Use of Controlled Atmospheres for Spectrographic Excitation Sources (40053). Many of the Project units are either wholly or partially completed and the following initial reports are available: Identification of Ferritin in Blood of Dogs Subjected to Radiation from an Atomic Detonation (UCLA-180); The Nutritional Value of Intravenous Tapioca Dextrin in Normal and Irradiated Rabbits (UCLA-181); The-Decarboxylation and Reconstitution of Linoleic Acid (UCLA-183); Preparation and Properties of Thymus Nucleic Acid (UCLA-184); The Radiation Chemistry of Cysteine Solutions Part II. (a) The Action of Sulfite on the Irradiated Solutions; (b) The Effect on Cystine (UCLA-185); A Revolving Specimen Stage for the Electron Microscope (UCLA-178); An Automatic Geiger-Mueller Tube Tester (UCLA-186); The Value of Gamma Radiation Dosimetry in Atomic Warfare Including a Discussion of Practical Dosage Ranges (UCLA-187); and A New Plastic Tape Film Badge Holder (UCLA-189). Two additional reports were issued; one by Dr. Wilbur Selle entitled Attempts to Alter the Response to Ionizing Radiations from the School of Medicine, UCLA (UCLA-176), and two, a restricted distribution report from the Alamogordo Section entitled Field Observations and Preliminary Field Data Obtained by the UCLA Survey Group on Operation Jangle, November 1951 (UCLA-182).
Date: April 10, 1952
Creator: Warren, S.L.
Partner: UNT Libraries Government Documents Department

An experimental investigation of two-phase crossflow over rigidly and flexibly mounted tubes

Description: Two-phase crossflow over heat exchanger tubes induces vibrations which contribute greatly to the wear on the tubes. Of the three mechanisms leading to two-phase flow-induced vibrations which have been identified, fluid-elastic instability has been recognized as that which leads to the vibrations with the largest amplitude. The mass damping parameter is used to predict the onset of fluid-elastic instability, and the mean drag coefficient is used to calculate the mass damping parameter. In this thesis, the drag coefficient measured over single tubes and tubes within array, in single-phase and two-phase flow at various Reynolds numbers, is discussed. The drag coefficient was measured by two methods. For flexibly mounted tubes, strain gages were mounted on cantilever beams which held the tube in place and allowed it to vibrate in the direction parallel to the flow only. For both rigidly and flexibly mounted tubes, pressure distributions were measured around the perimeter of the tube. Forces, and then the drag coefficient, could be calculated from this information. The drag coefficient was not found to depend upon the flexibility of the tube mounting. As the void fraction of the flow increases, the drag coefficient over the tube increases. This effect was found to be quite large at low Reynolds numbers, and weaker at higher Reynolds numbers, and a different effect was found at very high Reynolds numbers.
Date: December 31, 1991
Creator: Gerhart, S.M.
Partner: UNT Libraries Government Documents Department

Use of artificial intelligence in severe accident diagnosis for PWRs

Description: A combination approach of an expert system and neural networks is used to implement a prototype severe accident diagnostic system which would monitor the progression of the severe accident and provide necessary plant status information to assist the plant staff in accident management during the accident. The station blackout accident in a pressurized water reactor (PWR) is used as the study case. The current phase of research focus is on distinguishing different primary system failure modes and following the accident transient before and up to vessel breach.
Date: December 31, 1995
Creator: Wu, Zheng; Okrent, D. & Kastenberg, W.E.
Partner: UNT Libraries Government Documents Department

Use of Behaviorally Anchored Rating Scales (BARS) for deep technical knowledge

Description: The University of California at Los Angeles (UCLA) participated in a U.S. Nuclear Regulatory Commission research program to investigate methods to measure the effect of management and organization on nuclear plant safety. The UCLA research team focused its efforts on understanding {open_quotes}deep technical knowledge,{close_quotes} and its relation to probabilistic risk assessment. As a result, the research team combined deep technical knowledge with a commonly used rating system for understanding the effectiveness of management and organizations.
Date: December 31, 1993
Creator: Okrent, D.; Xions, Yongjie; Abbott, E.C. & Leonard, J.D. Jr.
Partner: UNT Libraries Government Documents Department

Fracture toughness of ordered intermetallic compounds exhibiting limited ductility and mechanical properties of ion-irradiated polycrystalline NiAl. Final report, July 1, 1986--June 30, 1997

Description: The focus of the research performed under the auspices of this grant changed several times during the lifetime of the project. The initial activity was an investigation of irradiation-induced amorphization of ordered intermetallic compounds, using energetic protons as the bombarding species. Two significant events stimulated a change of direction: (1) the proton accelerating facility that the authors had been using at the California State University at Los Angeles became unavailable late in 1988 because of a personnel matter involving the only individual capable of operating the machine; (2) they learned that disordering and amorphization of intermetallic compounds produced interesting effects on their mechanical properties. Loss of access t the local accelerator prompted a collaboration with Dr. Droa Pedraza of the Oak Ridge National Laboratory (ORNL), enabling access to the accelerator at ORNL. The influence of disordering and amorphization on mechanical properties ultimately stimulated the development of a miniaturized disk-bend testing (MDBT) facility, the intent of which was to provide semiquantitative and even quantitative measures of the mechanical behavior of ion-irradiated ordered intermetallic alloys. The second phase of the project involved the perfection and usage of the MDBT, and involved exploratory experiments on unirradiated materials like amorphous alloy ribbons and brittle grain boundaries in Ni{sub 3}Al. This report is a brief summary of the research highlights of the project, organized according to the activity that was emphasized at the time.
Date: September 1, 1997
Creator: Ardell, A.J.
Partner: UNT Libraries Government Documents Department

Impact of global climate change on ecosystem-level interactions among sympatric plants from all three photosynthetic pathways. Terminal report

Description: The proposed research will determine biochemical and physiological responses to variations in environmental factors for plants of all three photosynthetic pathways under competitive situations in the field. These responses will be used to predict the effects of global climatic change on an ecosystem in the northwestern Sonoran Desert where the C{sub 3} subshrub Encelia farinosa, the C{sub 4} bunchgrass Hilaria rigida, and the CAM succulent Agave deserti are co-dominants. These perennials are relatively short with overlapping shallow roots facilitating the experimental measurements as well as leading to competition for soil water. Net CO{sub 2} uptake over 24-h periods measured in the laboratory will be analyzed using an environmental productivity index (EPI) that can incorporate simultaneous effects of soil water, air temperature, and light. Based on EPI, net CO{sub 2} uptake and hence plant productivity will be predicted for the three species in the field under various treatments. Activity of the two CO{sub 2} fixation enzymes, Rubisco and PEPCase, will be determined for these various environmental conditions; also, partitioning of carbon to various organs will be measured based on {sup 14}CO{sub 2} labeling and dry weight analysis. Thus, enzymatic and partitioning controls on competition among sympatric model plants representing all three photosynthetic pathways will be investigated.
Date: December 17, 1997
Creator: Nobel, P.S.
Partner: UNT Libraries Government Documents Department

CO{sub 2} exchange, environmental productivity indices, and productivity of Agaves and Cacti under current and elevated atmospheric CO{sub 2} concentrations. Terminal report

Description: The research described in the proposal investigated net CO{sub 2} uptake and biomass accumulation for an extremely productive CAM plant, the prickly pear cactus Opuntia ficus-indica, under conditions of elevated CO{sub 2} concentrations for relatively long periods. The influences of soil water status, air temperature, and the photosynthetic photon flux (PPF) on net CO{sub 2} uptake over 24-h periods were evaluated to enable predictions to be made based on an Environmental Productivity Index (EPI). Specifically, EPI predicts the fraction of maximal daily net CO{sub 2} uptake based on prevailing environmental conditions. It is the product of indices for temperature, soil water, and intercepted PPF, each of which range from 0.00 when that index factor completely inhibits net CO{sub 2} uptake to 1.00 when no limitation occurs. For instance, the Water Index is 1.00 under wet conditions and decreases to 0.00 during prolonged drought. Although the major emphasis of the research was on net CO{sub 2} uptake and the resulting biomass production for O. ficus-indica, effects of elevated CO{sub 2} concentrations on root: shoot ratios and on the activities of the two carboxylating enzymes were also investigated. Moreover, experiments were also done on other CAM plants, including Agave deserti, Agave salmiana, and Hylocereus undatus, and Stenocereus queretaroensis.
Date: June 1, 1995
Partner: UNT Libraries Government Documents Department

CO{sub 2} exchange environmental productivity indices, and productivity of agaves and cacti under current and elevated atmospheric CO{sub 2} concentrations. Final report

Description: The research described in the proposal investigated net CO{sub 2} uptake and biomass accumulation for an extremely productive CAM plant, the prickly pear cactus Opuntia ficus-indica, under conditions of elevated CO{sub 2} concentrations for relatively long periods. The influences of soil water status, air temperature, and the photosynthetic photon flux (PPF) on net CO{sub 2} uptake over 24-h periods were evaluated to enable predictions to be made based on an Environmental Productivity Index (EPI). Specifically, EPI predicts the fraction of maximal daily net CO{sub 2} uptake based on prevailing environmental conditions. It is the product of indices for temperature, soil water, and intercepted PPF, each of which range from 0.00 when that index factor completely inhibits net CO{sub 2} uptake to 1.00 when no limitation occurs. For instance, the Water Index is 1.00 under wet conditions and decreases to 0.00 during prolonged drought. Although the major emphasis of the research was on net C0{sub 2} uptake and the resulting biomass production for O. ficus-indica, effects of elevated CO{sub 2} concentrations on root: shoot ratios and on the activities of the two carboxylating enzymes were also investigated. Moreover, experiments were also done on other CAM plants, including Agave deserti, Agave salmiana, and Hylocereus undatus, and Stenocereus queretaroensis.
Date: December 31, 1994
Creator: Nobel, P.S.
Partner: UNT Libraries Government Documents Department

Cross flow induced vibrations in staggered arrays of cylindrical structures

Description: Flow induced vibrations cause by instability is the subject of this investigation. The bulk of the work performed is theoretical in nature, the comparison with some of existing experimental data is given for each of four models described. First model encompasses the effects of prescribed motion on the cylinder. Such circumstances occur in the case of vortex shedding initiated instability. The reduced velocity within the cylinder array is low and there is no coupling between the adjacent cylinders. Second model assumes certain form of vibration and corresponding behavior of the perturbed velocity field in temporal and one of spatial coordinates thus transforming partial differential equations into ordinary differential equations and takes into account the motion of the neighboring cylinder. This corresponds to fluid elastic controlled instabilities. The resulting equations are solved analytically. The model is used for better understanding of the equations of cylinder motion as well as for quick estimates of threshold of instability. Third model relaxes an assumption about the form of vibration in spatial direction and uses the vorticity formulation of equation of fluid motion to account for fluid-solid interaction. This model analysis is of two phase (air-water mixture) flow. The void fraction distribution is found to be the single most decisive factor to determine the onset of instability for such a domain. In conclusion, two distinct mechanism were found to be responsible for flow induced vibration caused instabilities, (1) outside source controlled periodic excitation (such as vortex shedding) -- described by the first model and (2) fluid elastic forces -- described by second, third and fourth models. For the values of reduced velocity below 0.7 first model is proposed, for the values above 0.7, the rest.
Date: December 31, 1991
Creator: Marn, J.
Partner: UNT Libraries Government Documents Department

The radioisotope osteogram: Kinetic studies of skeletal disorders in humans

Description: Radioactive strontium can serve as a tracer to gain information concerning calcium metabolism in human subjects. Gamma-emitting Sr{sup 85} is used rather than the much more hazardous, beta-emitting Sr{sup 89} and Sr{sup 90}. (ca{sup 47} -- the ideal tracer for normal calcium -- is quite expensive and difficult to procure.) Very significant information may be obtained merely by measuring and recording the changes in radioactivity in various body areas during the first hour after intravenous injection of the bone-seeking radioisotope. This is accomplished by placing a lead-shielded gamma-scintillation detector in contact with the skin over the sites of interest and recording the activities on a scaler or ratemeter. The activity versus time curves so obtained are called radioisotope osteograms. Data were presented which indicated that Sr{sup 85} osteograms for patients afflicted with osteoporosis, Paget`s disease, tumor metastases to bone, and possibly multiple myeloma, differ significantly from those obtained from subjects with no skeletal abnormalities. Some interpretations of these deviations were discussed. The value of conducting double-tracer tests (e.g. -- Sr{sup 85} plus radio-iodinated serum albumin) was demonstrated, and correlations with excretion data were made. With further refinements the technique may ultimately become useful for certain diagnostic problems in the clinic and.for evaluating the efficacy of treatment of these disorders.
Date: October 16, 1959
Creator: MacDonald, N.S.
Partner: UNT Libraries Government Documents Department

An experimental study of fluidelastic instability and draf force on a tube in two-phase cross flow

Description: Two-phase cross flow over heat exchanger tubes creates vibrations which contribute greatly to the wear on the tubes. Fluidelastic instability is a major mechanism by which tubes can fail. In this work, the fluidelastic instability of a tube placed in an array subjected to two-phase cross flow has been studied. For the determination of fluidelastic instability, a triangular tube array was used. The tubes were made of acrylic and were 2.2 cm or 2.37 cm in diameter and 20 cm in length. Eighteen tubes and 4 half tubes formed 5 rows with a pitch to diameter ratio of 1.4. All of the tubes except the test tube were rigidly supported at the text section wall. The test tube was flexibly supported with two cantilever beams. By installing cantilever beams horizontally and vertically, drag and lift direction tube vibration were studied. Parameters of tube mass, structural stiffness, natural frequency, and pitch to diameter ratio were varied. The drag coefficients on a rigidly held tube in an array subjected to two-phase cross flow were measured. The tube in an array was located at displaced positions as well as at the normal position in order to study the variation of fluid force as the tube vibrates. In the experiments, gap Reynolds numbers up to 1 x 10{sup 5} were obtained, while void fraction was varied from zero to 0.5. The drag coefficients in two-phase flow are much higher than those in single phase flow. The ratio of two-phase to single phase drag coefficient decreases as Reynolds number increases. The drag coefficient on a tube in an array increases as the tube is displaced in the direction of flow. The drag coefficient increases rapidly when the tube is displaced more than a certain critical distance.
Date: December 31, 1994
Creator: Joo, Youngcheol
Partner: UNT Libraries Government Documents Department

Applications of mesoscopic physics to novel correlations and fluctuations of speckle patterns: Imaging and tomography with multiply scattered classical waves. Final report

Description: This is the final report on the grant, entitled `applications of mesoscopic physics to novel correlations and fluctuations of speckle patterns: imaging and tomography with multiply scattered classical waves`, which expired on September 14, 1994. The author summarizes the highlights of this research program, and lists the publications supported by this grant. The report is divided into sections, titled: application of mesoscopic fluctuations theory to correlations and fluctuations of multiply scattered light; quantum transport in localized electronic systems; electron-phonon inelastic scattering rate and the temperature scaling exponent in integer quantum Hall effect; high frequency quantum transport in quantum well devices.
Date: February 1, 1995
Creator: Feng, Shechao Charles
Partner: UNT Libraries Government Documents Department

Synchronous picosecond sonoluminescence: Developing and characterizing a new light source. Final report, December 1991--December 1994

Description: Sonoluminescence is the remarkable physical process whereby sound energy is transduced into light by the motion of a trapped bubble of gas in a liquid. Interest in sonoluminescence (or SL as we like to call it) is based upon our insight that sound energy must focus by over twelve orders of magnitude to make light. Thus SL is Nature`s most nonlinear oscillator.
Date: September 1, 1997
Creator: Putterman, S.J.
Partner: UNT Libraries Government Documents Department

Experimental observation of IFEL micro-bunching using coherent transition radiation

Description: Electron beam bunching in the optical wavelength was observed experimentally for the first time at the Brookhaven Accelerator Test Facility (ATF) using the Inverse Free Electron (IFEL) accelerator. The micro-bunched electron beam has been studied by measuring the coherent transition radiation (CTR). The authors have experimentally observed a quadratic dependency of the CTR signal with the charge of the electron beam and the observation distance.
Date: July 1997
Creator: Liu, Y.; Cline, D. B.; Wang, X. J. & Babzien, M.
Partner: UNT Libraries Government Documents Department

Micro-bunching diagnostics for the ICA by coherent transition radiation

Description: Here, the authors propose an effective method to detect micro-bunching effects (10 fs bunch length), produced by the ICA interaction, by using the CTR spectrum. The re-bunching of initially energy modulated e-beam passing through a Hydrogen gas cell (ICA interaction) is studied via a Monte Carlo simulation code (STI), as well as in a space-charge dominated region by a multi-particle time domain tracking code (PARMELA). The results show that even in a strong space-charge dominated region the re-bunching effect is still very pronounced. The erosion of bunching due to the space-charge defocusing washes out the final bunching peak only by about 10% (FWHM). The longitudinal distribution of a micro-bunched beam is Fourier analyzed to find the dominant harmonics contributing to the CTR. The CTR spectrum is calculated analytically for the ICA situation. A schematic of the experimental set up is also proposed.
Date: December 1995
Creator: Liu, Y.; Bogacz, S. A.; Cline, D. B.; Wang, X. J.; Pogorelsky, I. V. & Kimura, W. D.
Partner: UNT Libraries Government Documents Department

HEAT TRANSFER TO A BOILING LIQUID MECHANISM AND CORRELATIONS. Progress Report No. 7 (58-40)

Description: Various heat transfer mechanisms which have been previously proposed are analyzed in the light of recent experiments. Evidence is presented in favor of a liquid-vapor exchange mechanism and against the widely accepted "micro-convection" mechanism. The vapor-liquid exchange rnechanism is shown to explain the insensltivity of boiling heat flux to the level of subcooling. A "Reynolds Analogy" for nucleate boiling is presented in some detail. A procedure is given for calculating the superheat at which the liquid bulk velocity ceases to contribute to the heat flux. An expression for the growth of a vapor bubble in a highly superheated liquid is deduced. A method is presented which allows the deduction of correlations for nucleate boiling which give the dependence of heat flux on superheat and system pressure. Two such correlations are presented and results are compared with experiment. It is shown that one correlation yields the heat flux for different liquids varying from water to mercury, without necessitating any change in constant or exponent of the correlation. (auth)
Date: May 28, 1958
Creator: Forster, K. & Greif, R.
Partner: UNT Libraries Government Documents Department

Photocharge transport and recombination measurements in amorphous silicon films and solar cells by photoconductive frequency mixing. Annual subcontract report, 15 May 1995--15 May 1996

Description: Using the photomixing technique, the authors systematically studied the transport properties of intrinsic hydrogenated amorphous silicon (a-Si:H) samples that had hydrogen content ranging from over 10% to less than 1% and which were produced by the hot-wire technique at NREL. They investigated the continuous decay of electron drift mobility in intrinsic a-Si:H on light-soaking and determined the degradation of photoconductivity, lifetime, and drift mobility in these a-Si:H samples while light-soaking. In addition to the decay of the photoconductivity and electron lifetime, continuous decay of the electron drift mobility was found during the light-soaking process, which reveals a new phenomenon associated with the Staebler-Wronski effect. The drift mobility decreased by a factor of 2--4 for 5-hour light-soaking at 4-sun intensity. The authors investigated the effects of deposition conditions on transport properties of intrinsic a-Si:H films and, by using the photomixing technique, they determined the electron drift mobility, lifetime, and the conduction-band Urbach energy of a-Si:H films as a function of substrate temperature. 44 refs.
Date: October 1, 1996
Creator: Braunstein, R. & Dong, S.
Partner: UNT Libraries Government Documents Department

Plasma lens experiments at the final focus test beam

Description: The authors intend to carry out a series of plasma lens experiments at the Final Focus Test Beam facility at SLAC. These experiments will be the first to study the focusing of particle beams by plasma focusing devices in the parameter regime of interest for high energy colliders, and is expected to lead to plasma lens designs capable of unprecedented spot sizes. Plasma focusing of positron beams will be attempted for the first time. They will study the effects of lens aberrations due to various lens imperfections. Several approaches will be applied to create the plasma required including laser ionization and beam induced tunneling ionization of a working gas--the latter which has never been observed before. The compactness of the device should prove to be of interest for applications at the SLC and the next generation linear colliders.
Date: February 1, 1995
Creator: Barletta, W.; Chattopadhyay, S. & Chen, P.
Partner: UNT Libraries Government Documents Department

Unitarity-based techniques for one-loop calculations in QCD

Description: Perturbative QCD, and jet physics in particular, have matured sufficiently that rather than being merely subjects of experimental studies, they are now tools in the search for new physics. This role can be seen in the search for the top quark, as well as in recent speculations about the implications of supposed high-E{sub T} deviations of the inclusive-jet differential cross section at the Tevatron. One of the important challenges to both theorists and experimenters in coming years will be to hone jet physics as a tool in the quest for physics underlying the standard model. As such, it will be important to measurements of parameters of the theory or of non-perturbative quantities such as the parton distribution functions, as well as to searches for new physics at the LHC. Jet production, or jet production in association with identified photons or electroweak vector bosons, appears likely to provide the best information on the gluon distribution in the proton, and may also provide useful information on the strong coupling {alpha}{sub s}. In order to make use of these final states, the authors need a wider variety of higher-order calculations of matrix elements. Indeed, as the authors shall review, next-to-leading order calculations are in a certain sense the minimal useful ones. On the other hand, these calculations are quite difficult with conventional Feynman rules. In the following sections, the authors will discuss some of the techniques developed in recent years to simplify such calculations.
Date: June 1, 1996
Creator: Bern, Z.; Dixon, L. & Kosower, D.A.
Partner: UNT Libraries Government Documents Department

Transport in statistical media. Final report, May 1, 1988--May 1, 1990

Description: The technical content of these five papers is summarized in this report: Benchmark results for particle transport in a binary Markov statistical medium; Statistics, renewal theory, and particle transport; asymptotic limits of a statistical transport description; renormalized equations for linear transport in stochastic media; and solution methods for discrete state Markovian initial value problems.
Date: July 1, 1990
Creator: Pomraning, G.C.
Partner: UNT Libraries Government Documents Department

Efficient analytic computation of higher-order QCD amplitudes

Description: The authors review techniques simplifying the analytic calculation of one-loop QCD amplitudes with many external legs, for use in next-to-leading-order corrections to multi-jet processes. Particularly useful are the constraints imposed by perturbative unitarity, collinear singularities and a supersymmetry-inspired organization of helicity amplitudes. Certain sequences of one-loop helicity amplitudes with an arbitrary number of external gluons have been obtained using these constraints.
Date: March 1, 1995
Creator: Bern, Z.; Chalmers, G.; Dixon, L.; Dunbar, D.C. & Kosower, D.A.
Partner: UNT Libraries Government Documents Department

Electron acceleration in relativistic plasma waves generated by a single frequency short-pulse laser

Description: Experimental evidence for the acceleration of electrons in a relativistic plasma wave generated by Raman forward scattering (SRS-F) of a single-frequency short pulse laser are presented. A 1.053 {mu}m, 600 fsec, 5 TW laser was focused into a gas jet with a peak intensity of 8{times}10{sup 17} W/cm{sup 2}. At a plasma density of 2{times}10{sup 19} cm{sup {minus}3}, 2 MeV electrons were detected and their appearance was correlated with the anti-Stokes laser sideband generated by SRS-F. The results are in good agreement with 2-D PIC simulations. The use of short pulse lasers for making ultra-high gradient accelerators is explored.
Date: April 27, 1995
Creator: Coverdale, C.A.; Darrow, C.B.; Decker, C.D.; Mori, W.B.; Tzeng, K.C., Clayton, C.E.; Marsh, K.A. et al.
Partner: UNT Libraries Government Documents Department

Edge density modification with rf on TFTR and DIII-D

Description: Modification of the electron density profile in front of rf antennas has been observed on TFTR and DIII-D using reflectometers installed in-antenna to ensure localization to the antenna environment. The modification of the edge density gradient has two components: a flattening of the gradient in the private flux zone, and an increase in the edge density inside the last closed flux surface. In general, these modifications result in a significant decrease in the electron density over most of the private flux zone with a sharp rise in the density near the last closed flux surface. Data from TFTR is used to infer the dependence of this edge modification with antenna strap phasing and rf power. Initial results from DIII-D showing edge modification will also be discussed. Antenna modeling has shown that this modification in the private flux zone has only small effects on the antenna loading and launched spectrum.
Date: September 1, 1995
Creator: Hanson, G.R.; England, A.C. & Wilgen, J.B.
Partner: UNT Libraries Government Documents Department

Linear kinetic theory and particle transport in stochastic mixtures. Third year and final report, June 15, 1993--December 14, 1996

Description: The goal in this research was to continue the development of a comprehensive theory of linear transport/kinetic theory in a stochastic mixture of solids and immiscible fluids. Such a theory should predict the ensemble average and higher moments, such as the variance, of the particle or energy density described by the underlying transport/kinetic equation. The statistics studied correspond to N-state discrete random variables for the interaction coefficients and sources, with N denoting the number of components in the mixture. The mixing statistics considered were Markovian as well as more general statistics. In the absence of time dependence and scattering, the theory is well developed and described exactly by the master (Liouville) equation for Markovian mixing, and by renewal equations for non-Markovian mixing. The intent of this research was to generalize these treatments to include both time dependence and scattering. A further goal of this research was to develop approximate, but simpler, models from any comprehensive theory. In particular, a specific goal was to formulate a renormalized transport/kinetic theory of the usual nonstochastic form, but with effective interaction coefficients and sources to account for the stochastic nature of the problem. In the three and one-half year period of research summarized in this final report, they have made substantial progress in the development of a comprehensive theory of kinetic processes in stochastic mixtures. This progress is summarized in 16 archival journal articles, 7 published proceedings papers, and 2 comprehensive review articles. In addition, 17 oral presentations were made describing these research results.
Date: May 1, 1997
Creator: Pomraning, G.C.
Partner: UNT Libraries Government Documents Department