[Studies of non-linear dynamics of dissipative systems]. [Final report, April 1, 1988--October 31, 1989] (open access)

[Studies of non-linear dynamics of dissipative systems]. [Final report, April 1, 1988--October 31, 1989]

In the period of this grant I worked on three main areas: (1) Symmetries in inviscid flow equations in one, two, and three dimensions and related nonlinear stability theorems for these flows; (2) applications of Hamiltonian mechanics to the problems of shallow water equations and internal wave dynamics in oceanic flows; and, (3) analysis of signals from chaotic systems with an eye toward learning how to build models of chaotic systems in nature.
Date: September 10, 1990
Creator: Abarbanel, D. I.
Object Type: Report
System: The UNT Digital Library
(Studies of non-linear dynamics of dissipative systems) (open access)

(Studies of non-linear dynamics of dissipative systems)

In the period of this grant I worked on three main areas: (1) Symmetries in inviscid flow equations in one, two, and three dimensions and related nonlinear stability theorems for these flows; (2) applications of Hamiltonian mechanics to the problems of shallow water equations and internal wave dynamics in oceanic flows; and, (3) analysis of signals from chaotic systems with an eye toward learning how to build models of chaotic systems in nature.
Date: September 10, 1990
Creator: Abarbanel, D.I.
Object Type: Report
System: The UNT Digital Library
Study of electron-positron interactions (open access)

Study of electron-positron interactions

For the past seven years, this group has been interested in the study of tests of the Standard Model of Electroweak interactions. The program has centered about the AMY experiment which examines the nature of the final state products in electron-positron collisions in the center of mass energy range near 60 GeV. Results of these measurements have shown a remarkable consistency with the predictions of the minimal model of 3 quark and lepton generations and single charged and neutral intermediate bosons. No new particles or excited states have been observed nor has any evidence for departures in cross sections or angular asymmetries from expectations been observed. These conclusions have been even more firmly established by the higher energy results from the LEP and SLC colliders at center of mass energies of about 90 GeV. Our focus is shifting to the neutrino as a probe to electroweak interactions. The relative merit of attempting to observe neutrinos from point sources versus observing neutrinos generally is not easy to predict. The improved ability to interpret is offset by the probably episodic nature of the emission and irreproducibility of the results. In this phase of development, it is best to be sensitive to both …
Date: September 15, 1990
Creator: Abashian, A.; Gotow, K. & Philonen, L.
Object Type: Report
System: The UNT Digital Library
Velocity Measurements at Three Fish Screening Facilities in the Yakima Basin, Washington: Summer 1989 Annual Report. (open access)

Velocity Measurements at Three Fish Screening Facilities in the Yakima Basin, Washington: Summer 1989 Annual Report.

The Pacific Northwest Laboratory (PNL) measured the velocity conditions at three fish screening facilities in the Yakima River Basin: Wapato, Chandler, and Easton Screens. The measurement objectives were different at the three screens. At Wapato, approach and sweep velocities were measured to evaluate the effect of rearing pens in the screen forebay. A complete survey was performed at the Chandler Screens. At Easton, velocity was measured behind the screens to provide information for the installation of porosity boards to balance flow through the screens. Salmon-rearing pens used at the Wapato Canal had a minimal effect on the magnitude of approach and sweep velocities at the face of the drum screens, although the pens caused increased turbulence and variability in water velocities. The net pens did not appear to affect flows through the three fish bypasses. 8 refs., 17 figs., 5 tabs.
Date: September 1, 1990
Creator: Abernethy, C. Scott; Neitzel, Duane A. & Lusty, E. William
Object Type: Report
System: The UNT Digital Library
Quantitative non-destructive evaluation of high-temperature superconducting materials (open access)

Quantitative non-destructive evaluation of high-temperature superconducting materials

Even though the currently intensive research efforts on high-temperature superconducting materials have not yet converged on a well specified material, the strong indications are that such a material will be brittle, anisotropic, and may contain many flaws such as microcracks and voids at grain boundaries. Consequently, practical applications of high temperature superconducting materials will require a very careful strength analysis based on fracture mechanics considerations. Because of the high sensitivity of the strength of such materials to the presence of defects, methods of quantitative non-destructive evaluation may be expected to play an important role in strength determinations. This proposal is concerned with the use of ultrasonic methods to detect and characterize isolated cracks, clusters of microcracks and microcracks distributed throughout the material. Particular attention will be devoted to relating ultrasonic results directly to deterministic and statistical linear elastic fracture mechanics considerations.
Date: September 15, 1990
Creator: Achenbach, J. D.
Object Type: Report
System: The UNT Digital Library
Quantitative non-destructive evaluation of high-temperature superconducting materials. Technical progress report, September 1, 1989--August 30, 1990 (open access)

Quantitative non-destructive evaluation of high-temperature superconducting materials. Technical progress report, September 1, 1989--August 30, 1990

Even though the currently intensive research efforts on high-temperature superconducting materials have not yet converged on a well specified material, the strong indications are that such a material will be brittle, anisotropic, and may contain many flaws such as microcracks and voids at grain boundaries. Consequently, practical applications of high temperature superconducting materials will require a very careful strength analysis based on fracture mechanics considerations. Because of the high sensitivity of the strength of such materials to the presence of defects, methods of quantitative non-destructive evaluation may be expected to play an important role in strength determinations. This proposal is concerned with the use of ultrasonic methods to detect and characterize isolated cracks, clusters of microcracks and microcracks distributed throughout the material. Particular attention will be devoted to relating ultrasonic results directly to deterministic and statistical linear elastic fracture mechanics considerations.
Date: September 15, 1990
Creator: Achenbach, J. D.
Object Type: Report
System: The UNT Digital Library
Power Burst Facility/Boron Neutron Capture Therapy Program for cancer treatment (open access)

Power Burst Facility/Boron Neutron Capture Therapy Program for cancer treatment

This monthly bulletin describes activities in the following project areas during this reporting period: supporting technology development, large animal model studies, neutron source and facility preparation, administration and common support, and PBF operations. (FI)
Date: September 1, 1990
Creator: Ackermann, A.L. (ed.) & Dorn, R.V. III.
Object Type: Report
System: The UNT Digital Library
Advanced development of the spectrum sciences Model 5005-TF, single-event test fixture (open access)

Advanced development of the spectrum sciences Model 5005-TF, single-event test fixture

This report summarizes the advanced development of the Spectrum Sciences Model 5005-TF, Single-Event Test Fixture. The Model 5005-TF uses a Californium-252 (Cf-252) fission-fragment source to test integrated circuits and other devices for the effects of single-event phenomena. Particle identification methods commonly used in high-energy physics research and nuclear engineering have been incorporated into the Model 5005-TF for estimating the particle charge, mass, and energy parameters. All single-event phenomena observed in a device under test (DUT) are correlated with an identified fission fragment, and its linear energy transfer (LET) and range in the semiconductor material of the DUT.
Date: September 1, 1990
Creator: Ackermann, M.R.; Browning, J.S. (Sandia National Labs., Albuquerque, NM (USA)); Hughlock, B.W. (Boeing Aerospace and Electronics Co., Seattle, WA (USA)); Lum, G.K. (Lockheed Missiles and Space Co., Sunnyvale, CA (USA)); Tsacoyeanes, W.C. (Draper (Charles Stark) Lab., Inc., Cambridge, MA (USA)) & Weeks, M.D. (Spectrum Sciences, Inc., Santa Clara, CA (USA))
Object Type: Report
System: The UNT Digital Library
Transient diffusion of radionuclides from a cylindrical waste solid into fractured porous rock (open access)

Transient diffusion of radionuclides from a cylindrical waste solid into fractured porous rock

This paper presents the numerical results of an analytical study for mass transfer and transport of radionuclides released from a cylindrical waste solid into water-saturated fractured porous rock. The purposes of this study are (1) to predict the diffusive mass flux from a cylindrical waste solid into a planar fracture and the surrounding rock matrix for the low-flow conditions wherein near-field mass transfer is expected to be controlled by molecular diffusion and (2) to investigate the effects of cylindrical geometry and of multidimensional matrix diffusion including diffusion in the directions parallel to the fracture plane. In the paper are presented the derivation of an analytical solution for the time-dependent mass transfer from the cylinder for low-flow conditions and computer-code implementation and numerical results. The problem was first proposed and solved analytically by Chambre. Numerical results are shown for (1) the diffusive mass fluxes from the cylindrical waste solid into the fracture and into the rock matrix, (2) the diffusive mass flux across the rock/fracture interface, and (3) the instantaneous concentration isopleths in the fracture and in the rock matrix. Comparison of the present cylindrical model with previous planar models, wherein contaminant was assumed to be released only into the fracture …
Date: September 1, 1990
Creator: Ahn, J. (Tokyo Univ. (Japan). Faculty of Engineering); Chambre, P. L. & Pigford, T. H. (California Univ., Berkeley, CA (USA). Dept. of Nuclear Engineering Lawrence Berkeley Lab., CA (USA))
Object Type: Report
System: The UNT Digital Library
Top Quark Mass Spectrum From Flavor-Changing Processes (open access)

Top Quark Mass Spectrum From Flavor-Changing Processes

The input from flavor-changing processes is reviewed and results of several analyses are presented on the top quark mass spectrum without recourse to the neutral-current data. A top quark mass in the range 135 {plus minus} 25 GeV is much preferred, but a very massive top quark above 300 GeV can not be ruled out. Comments are made about the future use of the inclusive decay B {yields} {gamma} + X{sub S=1} for constraining the top quark mass. 24 refs., 2 figs.
Date: September 1990
Creator: Albright, Carl H.
Object Type: Article
System: The UNT Digital Library
Ion-induced grain growth in multilayer and coevaporated metal alloy thin films (open access)

Ion-induced grain growth in multilayer and coevaporated metal alloy thin films

Irradiation experiments were conducted on multilayer (ML) and coevaporated (CO) thin films in order to examine the role that the heat of mixing ({Delta}H{sub mix}) has in ion-induced grain growth. Room temperature irradiations using 1.7 MeV Xe were performed in the High Voltage Electron Microscope at Argonne National Laboratory. The alloys studied (Pt-Ti, Pt-V, Pt-Ni, Au-Co and Ni-Al) spanned a large range of {Delta}H{sub mix} values. Comparison of grain growth rates between ML and CO films of a given alloy confirmed a heat of mixing effect. Differences in grain growth rates between ML and CO films scaled according to the sign and magnitude of {Delta}H{sub mix} of the system (with exception of the Pt-V system). Substantial variations in growth rates among CO alloy films experiencing similar irradiation damage demonstrated that a purely collisional approach is inadequate for describing ion-induced grain growth and consideration must also be given to material-specific properties. Results from CO alloy films were consistent with a thermal spike model of ion-induced grain growth. The grain boundary mobility was observed to be proportional to the thermal spike-related parameter, (F{sub D}{sup 2})/({Delta}H{sub coh}{sup 3}), where F{sub D} is the deposited damage energy and {Delta}H{sub coh} is the cohesive energy.
Date: September 1, 1990
Creator: Alexander, D. E.; Was, G. S. & Rehn, L. E.
Object Type: Article
System: The UNT Digital Library
Engineering, installation, testing, and initial operation of the DIII-D Advanced Divertor (open access)

Engineering, installation, testing, and initial operation of the DIII-D Advanced Divertor

The Advanced Divertor (AD) for General Atomics tokamak, DIII-D, was installed in the summer of 1990. The AD has enabled two classes of physics experiments to be run: divertor biasing and divertor baffling. Both are new experiments for DIII-D. The AD has two principal components: (1) a continuous ring electrode; and (2) a toroidally symmetric baffle. The tokamak can be run in bias baffle or standard DIII-D divertor modes by accurate positioning of the outer divertor strike point through the use of the DIII-D control system. The paper covers design, analysis, fabrication, installation, instrumentation, testing, initial operation, and future plans for the Advanced Divertor from an engineering viewpoint. 2 refs., 5 figs.
Date: September 1, 1990
Creator: Andersen, P. M.; Baxi, C. B.; Reis, E. E.; Schaffer, M. J. & Smith, J. P.
Object Type: Article
System: The UNT Digital Library
Heavy Flavor Production in Fixed-Target Experiments (open access)

Heavy Flavor Production in Fixed-Target Experiments

This presentation is a review of recent measurements on charm production at fixed-target experiments. The measurements are relevant to a number of basic physics issues: tests of perturbative QCD, fragmentation, and basic hadronic structure. We now have high quality, high statistics data from several fixed-target experiments. These include a total of about 30,000 fully reconstructed open charm decays and even more copious J/{Psi}, {Psi}, and {Upsilon} decays. Reconstruction of the full data is now reaching completion and we await final results for systematic physics interpretations. This review of the current situation will be followed by a brief look beyond, toward beauty production at fixed-target experiments.
Date: September 1, 1990
Creator: Appel, J. A.
Object Type: Article
System: The UNT Digital Library
A miniature inexpensive, oxygen sensing element (open access)

A miniature inexpensive, oxygen sensing element

We have made good progress in formulating our procedures for assembly of prototype sensor parts to alleviate problems of oxidation/reduction of components and possibly deleterious interactions of component materials. We have been working exclusively with the simplest form of prototype, i.e. without an incorporated heater. This has been to save assembly time and materials and to simplify the system of the components while we have dealt with overriding, non-heater'' assembly issues. It is anticipated future inclusion of the heater will introduce some new problems to be overcome, but we do not think these will be overwhelming.
Date: September 30, 1990
Creator: Arenz, R.W.
Object Type: Report
System: The UNT Digital Library
Modified Seasonal Factors in Exponential Smoothing (open access)

Modified Seasonal Factors in Exponential Smoothing

Current practice uses statistical tests to determine whether seasonal factors should be applied in a given forecasting situation. Research suggests that an optimal policy might lie somewhere between using full seasonal factors and using no seasonal factors on series. This research proposes and tests use of a modified seasonality factor. Modified seasonal factors reduce the emphasis on the seasonal adjustments when forecasts are made. The adjustments account for errors in the estimation of the factors and for possible changes in the factors over the forecast horizon. An analysis of data from US Navy personnel inventories was conducted to test the use of a modified seasonality factor. Modified seasonal factors led to improved accuracy for predictions of inventories by paygrade using quarterly data from the Navy Personnel Research and Development Center (NPRDC). Under certain selections of factors, the mean absolute percent error (MAPE) was reduced by 4.4%. No gain was obtained, however, for the inventories by length of service. It is expected, but not shown here, that the modified seasonal factors will only be of value for series where the estimated seasonal factors show a substantial variation across the year. 3 refs., 6 tabs.
Date: September 1, 1990
Creator: Armstrong, J.S. (Pennsylvania Univ., Philadelphia, PA (USA). Wharton School of Finance and Commerce); Hwang, Ho-Ling (Oak Ridge National Lab., TN (USA)) & Bandy, J. (Tennessee Univ., Knoxville, TN (USA))
Object Type: Report
System: The UNT Digital Library
Projected implicit Runge-Kutta methods for differential-algebraic boundary value problems (open access)

Projected implicit Runge-Kutta methods for differential-algebraic boundary value problems

Differential-algebraic boundary value problems arise in the modelling of singular optimal control problems and in parameter estimation for singular systems. A new class of numerical methods for these problems is introduced, and shown to overcome difficulties with previously defined numerical methods. 4 refs., 1 tab.
Date: September 1, 1990
Creator: Ascher, U. (British Columbia Univ., Vancouver, BC (Canada)) & Petzoid, L. (Lawrence Livermore National Lab., CA (USA))
Object Type: Article
System: The UNT Digital Library
Numerical methods for boundary value problems in differential-algebraic equations (open access)

Numerical methods for boundary value problems in differential-algebraic equations

Differential-algebraic equation (DAE) boundary value problems arise in a variety of applications, including optimal control and parameter estimation for constrained systems. In this paper we survey these applications and explore some of the difficulties associated with solving the resulting DAE systems. For finite difference methods, the need to maintain stability in the differential part of the system often necessitates the use of methods based on symmetric discretizations. However, these methods can suffer from instability and loss of accuracy when applied to certain DAE systems. We describe a new class of methods, Projected Implicit Runge-Kutta Methods, which overcomes these difficulties. We give convergence and stability results, and present numerical experiments which illustrate the effectiveness of the new methods. 20 refs., 1 tab.
Date: September 24, 1990
Creator: Ascher, U.M. (British Columbia Univ., Vancouver, BC (Canada). Dept. of Computer Science) & Petzold, L.R. (Lawrence Livermore National Lab., CA (USA))
Object Type: Article
System: The UNT Digital Library
Calibration and Operation Schemes for CEBAF RF Control (open access)

Calibration and Operation Schemes for CEBAF RF Control

The RF control system for the CEBAF accelerator uses calibration tables to calibrate and linearize critical components in the RF control modules. This includes compensation for temperature drifts. Calibration data are stored in nonvolatile RAM on the CPU board in the control module. Algorithms for calibration of components like the vector modulator for the phase reference and the gradient detector are described. The calibration will be performed in a dedicated test stand which will be completely automated. The microprocessor in the control modules allows running of complex algorithms to achieve phase lock and optimize system gains for minimum residual errors for different gradients and beam loading.
Date: September 1, 1990
Creator: Ashkenazi, I.; Hovater, J.; Fugitt, Jock; Mahoney, Kelly & Simrock, Stefan
Object Type: Article
System: The UNT Digital Library
Selenium transformation in coal mine spoils (open access)

Selenium transformation in coal mine spoils

The objective of this part of the study is to investigate the oxidation-reduction (redox) environment that favor the release of selenium from coal mine spoils. It is anticipated that the study will help answer critical questions as to the form, solubility, and mobility of selenium from the spoil site to the surrounding environment. This investigation will evaluate the conditions which favor the speciation of selenium from coal mine spoils as affected by changes in the oxidation states of selenium.
Date: September 1, 1990
Creator: Atalay, A. & Koll, K. J.
Object Type: Report
System: The UNT Digital Library
Selenium transformation in coal mine spoils. Quarterly report (open access)

Selenium transformation in coal mine spoils. Quarterly report

The objective of this part of the study is to investigate the oxidation-reduction (redox) environment that favor the release of selenium from coal mine spoils. It is anticipated that the study will help answer critical questions as to the form, solubility, and mobility of selenium from the spoil site to the surrounding environment. This investigation will evaluate the conditions which favor the speciation of selenium from coal mine spoils as affected by changes in the oxidation states of selenium.
Date: September 1, 1990
Creator: Atalay, A. & Koll, K. J.
Object Type: Report
System: The UNT Digital Library
US--ITER activation analysis (open access)

US--ITER activation analysis

Activation analysis has been made for the US ITER design. The radioactivity and the decay heat have been calculated, during operation and after shutdown for the two ITER phases, the Physics Phase and the Technology Phase. The Physics Phase operates about 24 full power days (FPDs) at fusion power level of 1100 MW and the Technology Phase has 860 MW fusion power and operates for about 1360 FPDs. The point-wise gamma sources have been calculated everywhere in the reactor at several times after shutdown of the two phases and are then used to calculate the biological dose everywhere in the reactor. Activation calculations have been made also for ITER divertor. The results are presented for different continuous operation times and for only one pulse. The effect of the pulsed operation on the radioactivity is analyzed. 6 refs., 12 figs., 1 tab.
Date: September 1, 1990
Creator: Attaya, H.; Gohar, Y. & Smith, D.
Object Type: Article
System: The UNT Digital Library
Recommended methods for statistical analysis of data containing less-than-detectable measurements (open access)

Recommended methods for statistical analysis of data containing less-than-detectable measurements

This report is a manual for statistical workers dealing with environmental measurements, when some of the measurements are not given exactly but are only reported as less than detectable. For some statistical settings with such data, many methods have been proposed in the literature, while for others few or none have been proposed. This report gives a recommended method in each of the settings considered. The body of the report gives a brief description of each recommended method. Appendix A gives example programs using the statistical package SAS, for those methods that involve nonstandard methods. Appendix B presents the methods that were compared and the reasons for selecting each recommended method, and explains any fine points that might be of interest. This is an interim version. Future revisions will complete the recommendations. 34 refs., 2 figs., 11 tabs.
Date: September 1, 1990
Creator: Atwood, C. L.; Blackwood, L. G.; Harris, G. A. & Loehr, C. A.
Object Type: Report
System: The UNT Digital Library
Indoor air quality issues related to the acquisition of conservation in commercial buildings (open access)

Indoor air quality issues related to the acquisition of conservation in commercial buildings

The quality of indoor air in commercial buildings is dependent on the complex interaction between sources of indoor pollutants, environmental factors within buildings such as temperature and humidity, the removal of air pollutants by air-cleaning devices, and the removal and dilution of pollutants from outside air. To the extent that energy conservation measures (ECMs) may affect a number of these factors, the relationship between ECMs and indoor air quality is difficult to predict. Energy conservation measures may affect pollutant levels in other ways. Conservation measures, such as caulking and insulation, may introduce sources of indoor pollutants. Measures that reduce mechanical ventilation may allow pollutants to build up inside structures. Finally, heating, ventilation, and air-conditioning (HVAC) systems may provide surface areas for the growth of biogenic agents, or may encourage the dissemination of pollutants throughout a building. Information about indoor air quality and ventilation in both new and existing commercial buildings is summarized in this report. Sick building syndrome and specific pollutants are discussed, as are broader issues such as ventilation, general mitigation techniques, and the interaction between energy conservation activities and indoor air quality. Pacific Northwest Laboratory (PNL) prepared this review to aid the Bonneville Power Administration (Bonneville) in its …
Date: September 1, 1990
Creator: Baechler, M. C.; Hadley, D. L. & Marseille, T. J.
Object Type: Report
System: The UNT Digital Library
Polychlorinated biphenyls in commercial buildings (open access)

Polychlorinated biphenyls in commercial buildings

The Bonneville Power Administration (Bonneville) is planning to implement a conservation acquisition program in new and existing commercial buildings. In anticipation of that program, Bonneville is examining the potential environmental effects of conservation measures in commercial buildings. An important conservation measure is the installation of new energy-efficient lighting fixtures. Some of the old lighting fixtures that these new lights will be replacing were manufactured before 1978, when polychlorinated biphenyls (PCBs) were still used in the capacitors of the lighting ballasts. This report focuses on a summary of information about PCBs in fluorescent light fixtures manufactured before 1978. A key issue associated with these PCBs is the potential effect of lamp change-outs on ballast failure. The US Environmental Protection Agency (EPA) speculates that installing energy-efficient lamps in old, PCB-laden ballasts may contribute to ballast failure and PCB leaks, which is addressed in Section 3 of this report. Section 2 discusses applicable standards and regulations; Section 4 describes PCB concentrations in commercial buildings. Sections 5 and 6 discuss cleanup practices and disposal options. 4 tabs.
Date: September 1, 1990
Creator: Baechler, M.C.; Foley, L.O. & Jarnagin, R.E.
Object Type: Report
System: The UNT Digital Library