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Least cost planning from a customer's perspective (open access)

Least cost planning from a customer's perspective

In this paper, I offer some thoughts about least cost planning, not from the perspective of the regulator or utility, but from the perspective of a residential customer. The problem that I address is, as a homeowner in northern Virginia, I am about to make a long term fuel choice for my household, where the options include, natural gas, electricity and fuel oil. An additional choice is the energy efficiency capital investment in my home that could decrease my monthly fuel costs. My decision process, hopefully as a rational consumer, offers implications about the efficiency of various services provided by all three fuel suppliers, including the local natural gas distribution companies (LDC).
Date: March 2, 1992
Creator: Sutherland, R.J.
System: The UNT Digital Library
Analysis of oxygen on and in beryllium using 2 MeV helium ions (open access)

Analysis of oxygen on and in beryllium using 2 MeV helium ions

Analysis of oxygen on beryllium can be routinely performed using helium-ion backscattering (RBS). However, determination of the bulk oxygen concentration by this technique is limited to about 350 atomic parts per million (appM). We have performed simultaneous RBS and particle-induced x-ray emission (PIXE) measurements to improve the detection limit for bulk oxygen. The RBS measurements allowed determination of the surface oxygen before and after in-situ sputter cleaning by argon ions in an ultra-high-vacuum system. PIXE measurements of specimens with surfaces maintained clean by sputtering permitted assessment of the concentration of oxygen in the bulk. For our geometry and detector sensitivities, 90% of the oxygen x-ray signal originated in the first 2.1 ..mu..m of the beryllium and a detection limit of 10 appM was found. 12 refs., 3 figs.
Date: October 2, 1986
Creator: Musket, R.G.
System: The UNT Digital Library
Development and testing of an air quality model for Mexico City (open access)

Development and testing of an air quality model for Mexico City

Los Alamos National Laboratory and Instituto Mexicano del Petroleo have embarked on a joint study of options for improving air quality in Mexico City. The intent is to develop a modeling system which can address the behavior of pollutants in the region so that option for improving Mexico City air quality can be properly evaluated. In February of 1991, the project conducted a field program which yielded a variety of data which is being used to evaluate and improve the models. Normally the worst air quality for both primary and photochemical pollutants occurs in the winter Mexico City. During the field program, measurements included: (1) lidar measurements of aerosol transport and dispersion, (2) aircraft measurements of winds, turbulence, and chemical species aloft, (3) aircraft measurements of earth surface skin temperatures, and (4) tethersonde measurements of wind, temperature and ozone vertical profiles. A three-dimensional, prognostic, higher order turbulence meteorological model (HOTMAC) was modified to include an urban canopy and urban heat sources. HOTMAC is used to drive an Monte-Carlo kernel dispersion code (RAPTAD). HOTMAC also provides winds and mixing heights for the CIT photochemical model which was developed by investigators at the California Institute of Technology and Carnegie Mellon University.
Date: March 2, 1992
Creator: Williams, M. D.; Streit, G. (Los Alamos National Lab., NM (United States)); Cruz, X.; Ruiz, M.; Sosa, G. (Instituto Mexicano de Petroleo, Mexico City (Mexico)); Russell, A. G. et al.
System: The UNT Digital Library
Fusion power demonstration - a baseline for the mirror engineering test reactor (open access)

Fusion power demonstration - a baseline for the mirror engineering test reactor

Developing a definition of an engineering test reactor (ETR) is a current goal of the Office of Fusion Energy (OFE). As a baseline for the mirror ETR, the Fusion Power Demonstration (FPD) concept has been pursued at Lawrence Livermore National Laboratory (LLNL) in cooperation with Grumman Aerospace, TRW, and the Idaho National Engineering Laboratory. Envisioned as an intermediate step to fusion power applications, the FPD would achieve DT ignition in the central cell, after which blankets and power conversion would be added to produce net power. To achieve ignition, a minimum central cell length of 67.5 m is needed to supply the ion and alpha particles radial drift pumping losses in the transition region. The resulting fusion power is 360 MW. Low electron-cyclotron heating power of 12 MW, ion-cyclotron heating of 2.5 MW, and a sloshing ion beam power of 1.0 MW result in a net plasma Q of 22. A primary technological challenge is the 24-T, 45-cm bore choke coil, comprising a copper hybrid insert within a 15 to 18 T superconducting coil.
Date: December 2, 1983
Creator: Henning, C. D.; Logan, B. G.; Neef, W. S.; Dorn, D.; Clarkson, I. R.; Carpenter, T. et al.
System: The UNT Digital Library
Radiation-induced electrical breakdown of helium in fusion reactor superconducting magnet systems (open access)

Radiation-induced electrical breakdown of helium in fusion reactor superconducting magnet systems

A comprehensive theoretical study has been performed on the reduction of the electrical breakdown potential of liquid and gaseous helium under neutron and gamma radiation. Extension of the conventional Townsend breakdown theory indicates that radiation fields at the superconducting magnets of a typical fusion reactor are potentially capable of significantly reducing currently established (i.e., unirradiated) helium breakdown voltages. Emphasis is given to the implications of these results including future deployment choices of magnet cryogenic methods (e.g., pool-boiling versus forced-flow), the possible impact on magnet shielding requirements and the analogous situation for radiation-induced electrical breakdown in fusion RF transmission systems.
Date: December 2, 1983
Creator: Perkins, L.J.
System: The UNT Digital Library
Calculation of density profiles in tandem mirrors fueled by pellets (open access)

Calculation of density profiles in tandem mirrors fueled by pellets

We have modified the LLNL radial transport code TMT to model reactor regime plasmas, fueled by pellets. The source profiles arising from pellet fueling are obtained from existing pellet ablation models. Because inward radial diffusion due to inverted profiles must compete with trapping of central cell ions in the transition region for tandem mirrors, pellets must penetrate fairly far into the plasma. In fact, based on our radial calculations, a pellet with a velocity of 10 km/sec cannot sustain the central flux tubes; a velocity more like 100 km/sec will be necessary. We also find that the central cell radial diffusion must exceed classical by about a factor of 100.
Date: December 2, 1983
Creator: Campbell, R. B. & Gilmore, J. M.
System: The UNT Digital Library
Engineering problems in the development of fusion power reactors (open access)

Engineering problems in the development of fusion power reactors

This paper reviews current progress in the development of fusion power from the engineering point of view and highlights the most outstanding technical issues which must be resolved. (MOW)
Date: November 2, 1976
Creator: Varljen, T. C.
System: The UNT Digital Library
Recent results of studies of acceleration of compact toroids (open access)

Recent results of studies of acceleration of compact toroids

The observed gross stability and self-contained structure of compact toroids (CT's) give rise to the possibility, unique among magnetically confined plasmas, of translating CT's from their point of origin over distances many times their own length. This feature has led us to consider magnetic acceleration of CT's to directed kinetic energies much greater than their stored magnetic and thermal energies. A CT accelerator falls in the very broad gap between traditional particle accelerators at one extreme, which are limited in the number of particles per bunch by electrostatic repulsive forces, and mass accelerators such as rail guns at the other extreme, which accelerate many particles but are forced by the stress limitations of solids to far smaller accelerations. A typical CT has about a Coulomb of particles, weighs 10 micrograms and can be accelerated by magnetic forces of several tons, leading to an acceleration on the order of 10/sup 11/ gravities.
Date: March 2, 1984
Creator: Hammer, J. H.; Hartman, C. W. & Eddleman, J.
System: The UNT Digital Library
Dissociative recombination of interstellar ions: electronic structure calculations for HCO/sup +/ (open access)

Dissociative recombination of interstellar ions: electronic structure calculations for HCO/sup +/

The present study of the interstellar formyl ion HCO/sup +/ is the first attempt to investigate dissociative recombination for a triatomic molecular ion using an entirely theoretical approach. We describe a number of fairly extensive electronic structure calculations that were performed to determine the reaction mechanism of the e-HCO/sup +/ process. Similar calculations for the isoelectronic ions HOC/sup +/ and HN/sub 2//sup +/ are in progress. 60 refs.
Date: July 2, 1985
Creator: Kraemer, W.P. & Hazi, A.U.
System: The UNT Digital Library
Solution of the Field Equations for 2-D Electromagnetic Direct Implicit Plasma Simulation (open access)

Solution of the Field Equations for 2-D Electromagnetic Direct Implicit Plasma Simulation

A direct implicit particle-in-cell (PIC) simulation model with full electromagnetic (EM) effects has been implemented in 2-D Cartesian geometry. The model, implemented with the D/sub 1/ time differencing scheme, was first implemented in a 1-D electrostatic (ES) version to gain some experience with spatial differencing in forms suitable for extension to the full EM field in two dimensions. The implicit EM field solve is considerably different from the implicit ES code. The EM field calculation requires an inductive part as well as the electrostatic and the B field must be self-consistently advanced.
Date: January 2, 1985
Creator: Hewett, D. W. & Langdon, A. B.
System: The UNT Digital Library
Investigations of glass structure using fluorescence line narrowing and moleuclar dynamics simulations (open access)

Investigations of glass structure using fluorescence line narrowing and moleuclar dynamics simulations

The local structure at individual ion sites in simple and multicomponent glasses is simulated using methods of molecular dynamics. Computer simulations of fluoroberyllate glasses predict a range of ion separations and coordination numbers that increases with increasing complexity of the glass composition. This occurs at both glass forming and glass modifying cation sites. Laser-induced fluorescence line-narrowing techniques provide a unique probe of the local environments of selected subsets of ions and are used to measure site to site variations in the electronic energy levels and transition probabilities of rare earth ions. These and additional results from EXAFS, neutron and x-ray diffraction, and NMR experiments are compared with simulated glass structures.
Date: July 2, 1982
Creator: Weber, M. J. & Brawer, S. A.
System: The UNT Digital Library
Tomography of laser fusion plasmas (open access)

Tomography of laser fusion plasmas

Experimental programs exist in a number of laboratories throughout the world to test the feasibility of using powerful laser systems to drive the implosion of hydrogen isotope fuel to thermonuclear burn conditions. In a typical experiment multiple laser beams are focused onto a glass microshell (typically 50 ..mu..m to 200 ..mu..m diameter) filled with an equimolar D-T gas mixture. X-ray and particle emissions from the target provide important information about the hydrodynamic implosion of the glass shell and the associated compression and heating of the D-T fuel. Standard diagnostics for imaging such emissions are the grazing incidence reflection (GIR) x-ray microscope and the pinhole camera. Recently, a particular coded imaging technique, Zone Plate Coded Imaging (ZPCI), has been successfully used for x-ray and particle microscopy of laser fusion plasmas. ZPCI is highly attractive for investigating laser produced plasmas because it possesses a tomographic capability not shared by either the GIR or pinhole imaging techniques. This presentation provides a brief discussion of the tomographic potential of ZPCI. In addition, the first tomographic x-ray images (tomographic resolution approximately 74 ..mu..m) of a laser produced plasma are presented.
Date: August 2, 1977
Creator: Ceglio, N.M.
System: The UNT Digital Library
Tandem mirror fusion research (open access)

Tandem mirror fusion research

The tandem mirror program has evolved considerably in the last decade. Of significance is the viable reactor concept embodied in the MARS design. An aggressive experimental program, culminating in the operation of MFTF-B in late 1986, will provide a firm basis for refining the MARS design as necessary for constructing a reactor prototype in the 1990s.
Date: December 2, 1983
Creator: Baldwin, D.E.
System: The UNT Digital Library
Interfacing the tandem mirror reactor to the sulfur-iodine process for hydrogen production (open access)

Interfacing the tandem mirror reactor to the sulfur-iodine process for hydrogen production

The blanket is linked to the H/sub 2/SO/sub 4/ vaporization units and SO/sub 3/ decomposition reactor with either sodium or helium. The engineering and safety problems associated with these choices are discussed. This H/sub 2/SO/sub 4/ step uses about 90% of the TMR heat and is best close-coupled to the nuclear island. The rest of the process we propose to be driven by steam and does not require close-coupling. The sodium loop coupling seems to be preferable at this time. We can operate with a blanket around 1200 K and the SO/sub 3/ decomposer around 1050 K. This configuration offers double-barrier protection between Li-Na and the SO/sub 3/ process gases. Heat pipes offer an attractive alternate to provide an additional barrier, added modularity for increased reliability, and tritium concentration and isolation operations with very little thermal penalty.
Date: June 2, 1980
Creator: Galloway, T.R.
System: The UNT Digital Library
A Systematic Review of the Evidence Base for Telehospice (open access)

A Systematic Review of the Evidence Base for Telehospice

Article on a systematic review of the evidence base for telehospice.
Date: February 2, 2012
Creator: Oliver, Debra Parker; Demiris, George; Wittenberg-Lyles, Elaine; Washington, Karla T.; Day, Tami & Novak, Hannah
System: The UNT Digital Library
Design issues for a laboratory high gain fusion facility (open access)

Design issues for a laboratory high gain fusion facility

In an inertial fusion laboratory high gain facility, experiments will be carried out with up to 1000 MJ of thermonuclear yield. The experiment area of such a facility will include many systems and structures that will have to operate successfully in the difficult environment created by the sudden large energy release. This paper estimates many of the nuclear effects that will occur, discusses the implied design issues and suggests possible solutions so that a useful experimental facility can be built. 4 figs.
Date: November 2, 1987
Creator: Hogan, W.J.
System: The UNT Digital Library
Review of the state of the art in personnel neutron monitoring with solid state detectors (open access)

Review of the state of the art in personnel neutron monitoring with solid state detectors

Albedo systems are the mainstay at many facilities and continue to be refined. Advanced electrochemical etching techniques for CR-39 now yield a dose equivalent response that is nearly constant from 0.1 to 4.0 MeV. Recent studies include use of converters to enhance CR-39 response at both low and high energies. Methods have been suggested for use of CR-39, either alone or in conjunction with albedo and other detectors to provide spectral information as a step to more accurate dosimetry. Limitations in the use of CR-39 primarily center on the lack of consistent, high-quality, dosimetry-grade material, significant angular dependence, and poor dose equivalent response at both low and high energies. Work continues on silicon diodes, with some new designs. The most attractive new dosimetry technique is the bubble-damage or superheated drop detector. Metal-on-silicon (MOS) microelectronics present exciting possibilities for the future. 25 refs., 6 figs.
Date: October 2, 1987
Creator: Griffith, R.V.
System: The UNT Digital Library
Diagnostics developments and applications for laser fusion experiments (open access)

Diagnostics developments and applications for laser fusion experiments

Some diagnostics techniques applied to current laser fusion target experiments are reviewed. Specifically, holographic interferometry of target plasmas, coded aperture imaging of thermonuclear alpha-particles and neutron energy spectrum measurements are discussed.
Date: September 2, 1977
Creator: Coleman, L.W.
System: The UNT Digital Library
OCR vision system, an alternative to bar code (open access)

OCR vision system, an alternative to bar code

This report describes optical character reader system advantages and applications. Comparisons are made to bar code readers. (JDH)
Date: November 2, 1987
Creator: Leader, D R
System: The UNT Digital Library
Studies in tandem mirror theory. Paper IAEA-CN-38/F-4 (open access)

Studies in tandem mirror theory. Paper IAEA-CN-38/F-4

This paper discusses the formation, maintenance, and microstability of thermal barriers, which have been introduced as a means for improving tandem mirror reactor performance at reduced technological demands. It also describes calculations of tandem mirror central-cell ..beta.. limits due to MHD ballooning modes.
Date: June 2, 1980
Creator: Baldwin, D. E.; Cohen, R. H. & Cutler, T. A.
System: The UNT Digital Library
Tandem mirror experiment-upgrade vacuum system: a new configuration and operating parameters (open access)

Tandem mirror experiment-upgrade vacuum system: a new configuration and operating parameters

The Tandem Mirror Experiment-Upgrade (TMX-U) vacuum system has been installed and operating since December 1981. In 1982 and early 1983 the performance of the internal, dynamic pumping system was evaluated during physics experiments. The plasma region gas loads caused the pressure to exceed that allowable for achieving thermal barrier plasmas. The unified, multiple-beamline concept used on TMX-U to pump the neutral-beam injector gas was modified. The modifications to the system were designed to reduce conductance between the injectors and the plasma region to better use the differential pumping in the pumping regions. The modifications made were a smaller cross section neutralizer, replacing apertures with ducts between regions, eliminating the injector scrape-off in the plasma region, relocating the neutral beam dumps, and eliminating the gaps around various penetrations.
Date: December 2, 1983
Creator: Lang, D. D.; Calderon, M. O.; Hunt, A.; Nexsen, W. E.; Pickles, W. L. & Turner, W. C.
System: The UNT Digital Library
Optical analogs of model atoms in fields (open access)

Optical analogs of model atoms in fields

The equivalence of the paraxial wave equation to a time-dependent Schroedinger equation is exploited to construct optical analogs of model atoms in monochromatic fields. The approximation of geometrical optics provides the analog of the corresponding classical mechanics. Optical analogs of Rabi oscillations, photoionization, stabilization, and the Kramers-Henneberger transformation are discussed. One possibility for experimental realization of such optical analogs is proposed. These analogs may be useful for studies of quantum chaos'' when the ray trajectories are chaotic. 9 refs.
Date: May 2, 1991
Creator: Milonni, P.W.
System: The UNT Digital Library
TIBER II/ETR (Engineering Test Reactor) nuclear shielding and optional tritium breeding system: An overview (open access)

TIBER II/ETR (Engineering Test Reactor) nuclear shielding and optional tritium breeding system: An overview

TIBER II, the Tokamak Ignition/Burn Experimental Reactor II, is a design concept developed as the US candidate for an International Engineering Test Reactor (ETR). An important objective of this design is to minimize cost by minimizing major radius while providing a wall loading greater than 1.0 MW/m2 and a total fluence greater than 3.0 MWY/m2 needed for blanket module testing. The shielding required for the superconducting TF coils is an important element in setting TIBER II's 3.0m major radius. 6 refs., 1 fig., 1 tab.
Date: November 2, 1987
Creator: Lee, J. D. & Sawan, M.
System: The UNT Digital Library
Initial Results of the Tandem Mirror Experiment (TMX) at the Lawrence Livermore Laboratory (open access)

Initial Results of the Tandem Mirror Experiment (TMX) at the Lawrence Livermore Laboratory

Initial experimental results from the Tandem Mirror Experiment (TMX) are presented. Axial profiles of the plasma density and potential necessary for electrostatically enhanced confinement of the central-cell ions have been generated and sustained for the duration of neutral-beam injection. The resulting central-cell ion confinement against axial loss is improved by a factor as large as 9 above that given by magnetic confinement alone. The plasma exhibits gross magnetohydrodynamic stability and microstability. Under some conditions, a residual level of ion cyclotron fluctuations in the end cells heats the central-cell ions and degrades their confinement.
Date: April 2, 1980
Creator: Grubb, D. P.; Anderson, C. A.; Casper, T. A.; Clauser, J. F.; Coensgen, F. H.; Correll, D. L. et al.
System: The UNT Digital Library