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Economic Analysis of Ilumex, A Project to Promote Energy-Efficient Residential Lighting in Mexico (open access)

Economic Analysis of Ilumex, A Project to Promote Energy-Efficient Residential Lighting in Mexico

A higher penetration of compact fluorescent lamps (CFLs) for household lighting can reduce growth in peak electricity demand, reduce sales of subsidized electricity, and lessen environmental impacts. This paper describes an economic analysis of a project designed to promote high penetration rates of CFLs in two cities in Mexico. Our analysis indicates that the project will bring substantial net economic benefits to Mexico, the utility, and the average customer. In the absence of any subsidy to CFLs, most customers will see a payback period longer than two years. By sharing some of the anticipated net benefit, CFE, the utility company, can reduce the payback period to a maximum of two years for all customers. CFE's role is thus crucial to the successful implementation of the project. Expanding the Ilumex project to a Mexico-wide program would make a significant contribution towards meeting the planned addition of generation capacity by the year 2000.
Date: November 1, 1993
Creator: Sathaye, Jayant A.; Friedmann, R.; Meyers, S.; de Buen, O.; Gadgil, A. J.; Vargas, E. et al.
System: The UNT Digital Library
GAMMASPHERE: Correction technique for detector charge trapping (open access)

GAMMASPHERE: Correction technique for detector charge trapping

GAMMASPHERE uses 110 very large germanium detectors. Such detectors exhibit charge trapping effects on energy resolution initially due to a native electron trap that is present in virtually all germanium. Furthermore, radiation damage is a serious problem in GAMMASPHERE experiments, producing hole traps that degrade resolution and eventually require annealing to restore the original performance. The technique discussed here uses the current pulse shape from a detector to develop a parameter related to the radius of the largest interaction in the ``track`` of a gamma ray in the detector. Since the charge trapping loss in a signal can be related to the distance carriers travel, the ``radius`` parameter can be used by software to apply a trap correction to the signal.
Date: November 1, 1993
Creator: Goulding, F. S. & Landis, D. A.
System: The UNT Digital Library
Chemometric analysis of infrared emission spectra for quantitative analysis of BPSG films on silicon (open access)

Chemometric analysis of infrared emission spectra for quantitative analysis of BPSG films on silicon

Infrared emission spectra of 21 borophosphosilicate glass (BPSG) thin films on silicon wafers were collected with the samples held at constant temperature between 125--400{degree}C using a heating stage designed for precise temperature control ({plus_minus}{degree}C). Partial test squares calibrations applied to the BPSG infrared emittance spectra allowed four BPSG thin-film properties to be simultaneously quantified with precisions of 0.1 wt. % for boron and phosphorus, 35 {Angstrom} for film thickness, and 1.2{degree}C for temperature.
Date: November 1, 1993
Creator: Franke, J. E.; Chen, Chuenyuan S.; Zhang, Songbaio; Niemczyk, T. M. & Haaland, D. M.
System: The UNT Digital Library
Preventing pollution from plutonium processing (open access)

Preventing pollution from plutonium processing

The plutonium processing facility at Los Alamos has adopted the strategic goal of becoming a facility that processes plutonium in a way that produces only environmentally benign waste streams. Pollution prevention through source reduction and environmentally sound recycling are being pursued. General approaches to waste reductions are administrative controls, modification of process technologies, and additional waste polishing. Recycling of waste materials, such as spent acids and salts, are technical possibilities and are being pursued to accomplish additional waste reduction. Liquid waste stream polishing to remove final traces of plutonium and hazardous chemical constituents is accomplished through (a) process modifications, (b) use of alternative chemicals and sorbents for residue removal, (c) acid recycling, and (d) judicious use of a variety of waste polishing technologies. Technologies that show promise in waste minimization and pollution prevention are identified. Working toward this goal of pollution prevention is a worthwhile endeavor, not only for Los Alamos, but for the Nuclear Complex of the future.
Date: November 1, 1993
Creator: Pillay, K. K. S.
System: The UNT Digital Library
Distributing functionality in the Drift Scan Camera System (open access)

Distributing functionality in the Drift Scan Camera System

The Drift Scan Camera (DSC) System acquires image data from a CCD camera. The DSC is divided physically into two subsystems which are tightly coupled to each other. Functionality is split between these two subsystems: the front-end performs data acquisition while the host subsystem performs near real-time data analysis and control. Yet, through the use of backplane-based Remote Procedure Calls, the feel of one coherent system is preserved. Observers can control data acquisition, archiving to tape, and other functions from the host, but, the front-end can accept these same commands and operate independently. The DSC meets the needs for such robustness and cost-effective computing.
Date: November 1, 1993
Creator: Nicinski, T.; Constanta-Fanourakis, P.; MacKinnon, B.; Petravick, D.; Pluquet, C.; Rechenmacher, R. et al.
System: The UNT Digital Library
Risk management at Los Alamos National Laboratory (open access)

Risk management at Los Alamos National Laboratory

Los Alamos National Laboratory has risk management programs at a number of administrative levels. Each line organization has responsibility for risk management for routine operations. The Facility Risk Management group (HS-3) is the Los Alamos organization with the primary responsibility for risk management including providing input and expertise to facilities and line managers in the management and documentation of ES&H hazards and risks associated with existing and new activities. One of the major contributions this group has made to laboratory risk management program is to develop and implement a hazard identification and classification methodology that is readily adaptable to continuously changing classification guidelines such as DOE-STD-1027. The increased emphasis on safety at Los Alamos has led to the formation of additional safety oversight organization such as the Integration and Coordination Office (ICO), which is responsible for prioritization of risk management activities. In the fall of 1991, nearly 170 DOE inspectors spent 6 weeks analyzing the environmental, safety, and health activities at Los Alamos. The result of this audit was a list of over 1000 findings, each indicating some deficiency in current Laboratory operations relative to DOE and other government regulation. The audit team`s findings were consolidated and ``action plans`` were …
Date: November 1, 1993
Creator: Brooks, D. G. & Stack, D. W.
System: The UNT Digital Library
The advanced PFB process: Pilot plant results and design studies (open access)

The advanced PFB process: Pilot plant results and design studies

The plant being developed is a hybrid of two technologies; it incorporates the partial gasification of coal in a vessel called the carbonizer and the combustion of the resultant char residue in a circulating pressurized fluidized bed combustor (CPFBC). In this plant, coal is fed to a pressurized carbonizer that produces a low-Btu fuel gas and char. After passing through a cyclone and a ceramic barrier filter to remove gas-entrained particulates, the fuel gas is burned in a topping combustor to produce the energy required to drive a gas turbine. The gas turbine drives a generator and a compressor that feeds air to the carbonizer, a CPFBC, and a fluidized bed heat exchanger (FBHE). The carbonizer char is burned in the CPFBC with high excess air. The vitiated air from the CPFBC supports combustion of the fuel gas in the gas turbine topping combustor. Steam generated in a heat-recovery steam generator (HRSG) downstream of the gas turbine and in the FBHE associated with the CPFBC drives the steam turbine generator that furnishes the balance of electric power delivered by the plant. The low-Btu gas is produced in the carbonizer by pyrolysis/mild devolatilization of coal in a fluidized bed reactor. Because …
Date: November 1, 1993
Creator: Robertson, A.; Domeracki, W.; Horazak, D.; Newby, R. & Rehmat, A.
System: The UNT Digital Library
B production and B{sup 0}{bar B}{sup 0} mixing at D0 (open access)

B production and B{sup 0}{bar B}{sup 0} mixing at D0

Preliminary results on B physics studies from the D0 experiment at the Fermilab collider are presented. Single and dimuon events produced in p{bar p} collisions at {radical}s = 1.8 TeV were used in the analysis. Inclusive single muon and J/{Psi} differential cross sections are shown. The results of a measurement of the time averaged B{sup 0}{bar B}{sup 0} to mixing parameter are presented.
Date: November 1, 1993
Creator: Denisov, D.
System: The UNT Digital Library
Initial measurements with an actively cooled calorimeter in a large pool fire (open access)

Initial measurements with an actively cooled calorimeter in a large pool fire

The initial measurements with a 1 m {times} 1 m water cooled vertical flat plate calorimeter located 0.8 m above and inside a 6 m {times} 6 m JP-4 pool fire are described. Heat fluxes in ten vertical 0. 1 m high {times} 1 m wide zones were measured by means of water calorimetry in quasi-steady-state. The calorimeter face also included an array of intrinsic thermocouples to measure surface temperatures, and an array of Schmidt-Boelter radiometers for a second, more responsive, method of heat flux measurement. Other experimental measurement devices within the pool fire included velocity probes, directional flame thermometers (DFTs), and thermocouples. Water calorimetry indicated heat fluxes of about 65 to 70 kW/m{sup 2} with a gradual decrease with increasing height above the pool. Intrinsic thermocouple measurements recorded typical calorimeter surface temperatures of about 500{degrees}C, with spatial variations of {plus_minus}150{degrees}C. Gas velocities across the calorimeter face averaged 3.4 m/s with a predominant upward component, but with an off-vertical skew. Temperatures of 800 to 1100{degrees}C were measured with the DFTS. The observed decrease in heat flux with increasing vertical height is consistent with analytical fire models derived for constant temperature surfaces. Results from several diagnostics also indicated trends and provided …
Date: November 1, 1993
Creator: Koski, J. A.; Kent, L. A. & Wix, S. D.
System: The UNT Digital Library
Soils and groundwater cleanup at Fernald: A status update on Operable Unit No. 5 (open access)

Soils and groundwater cleanup at Fernald: A status update on Operable Unit No. 5

This report discusses a status update on the cleanup operations at FERNALD. Discussed is the regulatory framework for FERNALD cleanup; overview of the FERNALD site; description of operable unit 5;remedial investigation; pattern of contamination; feasibility studies; and tangible progress to date.
Date: November 1, 1993
Creator: Yerace, P. J.; Bomberger, A. K. & Brettschneider, D. J.
System: The UNT Digital Library
The identification of inflow fluid dynamics parameters that can be used to scale fatigue loading spectra of wind turbine structural components (open access)

The identification of inflow fluid dynamics parameters that can be used to scale fatigue loading spectra of wind turbine structural components

We have recently shown that the alternating load fatigue distributions measured at several locations on a wind turbine operating in a turbulent flow can be described by a mixture of at least three parametric statistical models. The rainflow cycle counting of the horizontal and vertical inflow components results in a similar mixture describing the cyclic content of the wind. We believe such a description highlights the degree of non-Gaussian characteristics of the flow. We present evidence that the severity of the low-cycle, high-amplitude alternating stress loads seen by wind turbine components are a direct consequence of the degree of departure from normality in the inflow. We have examined the details of the turbulent inflow associated with series large loading events that took place on two adjacent wind turbines installed in a large wind park in San Gorgonio Pass, California. In this paper, we describe what we believe to be the agents in the flow that induced such events. We also discuss the atmospheric mechanisms that influence the low-cycle, high-amplitude range loading seen by a number of critical wind turbine components. We further present results that can be used to scale the specific distribution shape as functions of measured inflow fluid …
Date: November 1, 1993
Creator: Kelley, N. D.
System: The UNT Digital Library
Industry/University Consortium for ATS research (open access)

Industry/University Consortium for ATS research

The Industry/University ATS research program is the result of two planning workshops. Workshop I was held April 8--10, 1991 and had the goal of identifying research needs for advanced gas turbine cycles that would permit rapid commercialization of cycles with significant improvements over the machines currently under development, in terms of the cost of electricity produced and the environmental burdens resulting from their use in power producing. Workshop II was held in January 1992 and continued the identification of the research needs to develop advanced gas turbine systems. The goals established for the ATS systems were: (1) efficiency exceeding 60% for large utility turbine system and 15% improvement in heat rate for industrial systems; (2) busbar energy costs 10% less than current state of the art and (3) fuel flexible designs. In addition Workshop II participants agreed that an industry driven research consortium was an acceptable mechanism to achieve base technology development needs.
Date: November 1, 1993
Creator: Allen, R. P. & Golan, L. P.
System: The UNT Digital Library
Simulation of penetration and perforation with CTH (open access)

Simulation of penetration and perforation with CTH

This report provides the status and results of the NRC Thermoluminescent Dosimeter (TLD) Direct Radiation Monitoring Network. It presents the radiation levels measured in the vicinity of NRC licensed facilities throughout the country for the third quarter of 1993.
Date: November 1, 1993
Creator: Silling, S. A.
System: The UNT Digital Library
Effect of aluminate ions on the heat of hydration of cementitious waste forms (open access)

Effect of aluminate ions on the heat of hydration of cementitious waste forms

During the hydration and setting of high-salt content liquid waste grouts, considerable heat is generated by exothermic reactions within the grout. These reactions include hydration reactions of cementitious solids and reactions between waste constituents and the solids. Adiabatic temperature rises exceeding 80{degrees}C have been estimated for grouts prepared with a dry blend of 47 wt % fly ash, 47 wt % blast furnace slag, and 6 wt % type I/II Portland cement (1) Performance criteria for grout disposal specify that the temperature of the grout waste form must not exceed 90{degrees}C (2) To counter the increase in temperature, inert solids were added to the ``47/47/6`` dry blend to reduce the amount of heat-generating solids, thereby decreasing the temperature rise. Based on preliminary results from adiabatic calorimetry, a dry blend consisting of 40 wt % limestone flour, 28 wt % class F fly ash, 28 wt % ground blast furnace slag, and 4 wt % type I/II Portland cement was selected for further testing.
Date: November 1, 1993
Creator: Lokken, R. O.
System: The UNT Digital Library
Dual-band infrared imaging for quantitative corrosion detection in aging aircraft (open access)

Dual-band infrared imaging for quantitative corrosion detection in aging aircraft

Aircraft skin thickness-loss from corrosion has been measured using dual-band infrared (DBIR) imaging on a flash-heated Boeing 737 fuselage structure. We mapped surface temperature differences of 0.2 to 0.6 {degrees}C for 5 to 14% thickness losses within corroded lap splices at 0.4 seconds after the heat flash. Our procedure mapped surface temperature differences at sites without surface-emissivity clutter (from dirt, dents, tape, markings, ink, sealants, uneven paint, paint stripper, exposed metal and roughness variations). We established the correlation of percent thickness loss with surface temperature rise using a partially corroded F-18 wing box and several aluminum panels which had thickness losses from milled flat-bottom holes. We mapped the lap splice composite thermal inertia, (kpc){sup {1/2}}, which characterized shallow skin defects within the lap splice at early times (<0.3 s) and deeper skin defects within the lap splice at late times (>0.4 s). Corrosion invaded the inside of the Boeing 737 lap splice, beneath the galley and the latrine, where we observed ``pillowing`` from volume build-up of corrosion by-products.
Date: November 1, 1993
Creator: Del Grande, N. K.
System: The UNT Digital Library
Results and insights from the low power and shutdown Level 1 PRA of the Grand Gulf Nuclear Power Station (open access)

Results and insights from the low power and shutdown Level 1 PRA of the Grand Gulf Nuclear Power Station

The US Nuclear Regulatory Commission`s Office of Nuclear Regulatory Research has undertaken a two-phase project to analyze the frequencies, consequences, and risk of accidents occurring during modes of operation other than full power (i.e., low power and shutdown (LP&S) conditions). The Phase 1 work represented a ``coarse screening`` of all identified modes of operation. The results were used to identify which set of plant operating conditions would be subjected to a detailed analysis during Phase 2. This paper presents an overview of the results from the current Phase 2 effort to identify and quantify the various accident sequences that can lead to severe core damage. This overview encompasses the detailed analysis of potential accidents that could occur at the Grand Gulf Nuclear Power Plant while in the Cold Shutdown Phase [Plant Operational State (POS) 5] of a refueling outage.
Date: November 1, 1993
Creator: Whitehead, D. W.; Staple, B. D.; Daniel, S. L.; Darby, J.; Miller, S.; Forester, J. et al.
System: The UNT Digital Library
Production of {phi} mesons in central Si + Au collisions at 14.6 A{center_dot}GeV/c (open access)

Production of {phi} mesons in central Si + Au collisions at 14.6 A{center_dot}GeV/c

The production of {phi} mesons from, central Si + Au collisions has been measured by E859 at the BNL-AGS by selecting events with identified K{sup +}K{sup {minus}} pairs. The values for the mass and width of the {phi} obtained from the invariant mass of the kaon pairs are consistent with those of the Particle Data Book. Preliminary results for the invariant 1/2{pi}m{sub T} d{sup 2}n/dm{sub T}dy distribution and dN/dy are presented.
Date: November 1, 1993
Creator: Wang, Yufeng & Collaboration, E-802
System: The UNT Digital Library
Practical problems in aggregating expert opinions (open access)

Practical problems in aggregating expert opinions

Expert opinion is data given by a qualified person in response to a technical question. In these analyses, expert opinion provides information where other data are either sparse or non-existent. Improvements in forecasting result from the advantageous addition of expert opinion to observed data in many areas, such as meteorology and econometrics. More generally, analyses of large, complex systems often involve experts on various components of the system supplying input to a decision process; applications include such wide-ranging areas as nuclear reactor safety, management science, and seismology. For large or complex applications, no single expert may be knowledgeable enough about the entire application. In other problems, decision makers may find it comforting that a consensus or aggregation of opinions is usually better than a single opinion. Many risk and reliability studies require a single estimate for modeling, analysis, reporting, and decision making purposes. For problems with large uncertainties, the strategy of combining as diverse a set of experts as possible hedges against underestimation of that uncertainty. Decision makers are frequently faced with the task of selecting the experts and combining their opinions. However, the aggregation is often the responsibility of an analyst. Whether the decision maker or the analyst does …
Date: November 1, 1993
Creator: Booker, J. M.; Picard, R. R. & Meyer, M. A.
System: The UNT Digital Library
Trace organic chemical detection using an ultraviolet excitation molecular beam fluorometer (open access)

Trace organic chemical detection using an ultraviolet excitation molecular beam fluorometer

Detection of air-borne environmental contaminants, such as organic solvents, requires unambiguous compound identification and sensitivity to concentrations below those permitted by regulating agencies. One promising detection approach uses a pulsed supersonic molecular beam vacuum expansion in combination with fluorescence signal spectral analysis to identify species in a chemical mixture. This report describes the use and performance of the ultraviolet excitation molecular beam fluorometer.
Date: November 1, 1993
Creator: Preppernau, B. L. & Hargis, P. J.
System: The UNT Digital Library
Analysis of Offgassed Water: Calibration and Techniques (open access)

Analysis of Offgassed Water: Calibration and Techniques

Analysis of water in vacuum systems presents large difficulties. Generation of known partial pressures is necessary to calibrate mass spectrometer response for quantitative analysis. For this purpose, two designs of leaks and their calibrations will be described. Two problems of offgas analyses dictated the development of special techniques. One study, examining comparative surface desorption, required rapid sample insertion and data acquisition. The other study, the monitoring of slowly changing offgas rates, required high precision over extended periods. Very constant, elevated temperatures of the entire vacuum system are required to keep the water partial pressure a function of current sample offgassing. Exposure of mass spectrometers to water can cause instabilities to their sensitivities to all gases. Methods of decreasing this effect through ionizer modification and of acquiring good data through special calibration procedures will be described.
Date: November 1, 1993
Creator: Basford, J. A.
System: The UNT Digital Library
Towards a theory of growing surfaces: Mapping two-dimensional Laplacian growth onto Hamiltonian dynamics and statistics (open access)

Towards a theory of growing surfaces: Mapping two-dimensional Laplacian growth onto Hamiltonian dynamics and statistics

I show that the evolution of a two dimensional surface in a Laplacian field can be described by Hamiltonian dynamics. First the growing region is mapped conformally to the interior of the unit circle, creating in the process a set of mathematical zeros and poles that evolve dynamically as the surface grows. Then the dynamics of these quasi-particles are transformed into a seperable action-angle Hamiltonian that describes an orbital motion on a torus. A specific case is discussed explicitly, which demonstrates the integrability of the surface-tension-free Laplacian growth process. This formulation holds as long as the singularities of the map are confined to within the unit circle. This approach further allows for surface tension to be introduced as an energetic term in the resulting Hamiltonian which effects repulsion between the quasi-particles and the surface. These results are used here to formulate a first-principles statistical theory of pattern formation in stochastic growth, where noise is a key player.
Date: November 1, 1993
Creator: Blumenfeld, R.
System: The UNT Digital Library
Impact of observed hyperfine splitting on X-ray laser gain (open access)

Impact of observed hyperfine splitting on X-ray laser gain

Line broadening mechanisms play an important role in determining the gain of X-ray laser transitions. Typically Doppler broadening is the primary mechanism which determines the linewidth of these transitions. However, the authors present cases where the hyperfine effect is the dominant line broadening mechanism. Studying laser lines, which tend to have gain narrowed linewidths, enables one to observe these dramatic hyperfine effects which would be difficult to observe in opacity or Stark broadened lines. In this work the authors report the observation of hyperfine splitting on an X-ray laser transition and discuss how hyperfine splitting has a major impact on the laser gain. In the experiments they measure the lineshape of the 3p {yields} 3s, J = 0 {yields} 1 transition in neon-like niobium and zirconium and observe a 28 m{angstrom} splitting between the two largest hyperfine components in the niobium(Z=41) line at 145.9{angstrom}, in good agreement with theory. In zirconium(Z=40), no splitting is observed since the hyperfine effect is proportional to the nuclear moment, and zirconium has zero nuclear moment, as is typical for even-Z elements. The hyperfine effect is shown to effect transitions which have a 2p{sub 1/2} vacancy in the closed neon-like core much more than those …
Date: November 1, 1993
Creator: Nilsen, J.; Koch, J. A.; Scofield, J. H.; MacGowan, B. J.; Moreno, J. C. & Da Silva, L. B.
System: The UNT Digital Library
The effect of processing on the microstructure of Ag-sheathed Bi-2223 wires (open access)

The effect of processing on the microstructure of Ag-sheathed Bi-2223 wires

Studies using TEM and SEM, focused on effect of final heat treatment conditions on microstructure of (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x}(Bi-2223)wires and corresponding variations in critical currents (I{sub c}). It is found that variations in I{sub c} for segments cut from various points along length of a wire can be correlated with variations in volume fraction and nature of second phases. Similar variations are observed between wires processed under different final annealing conditions. A common feature found in all of the wire segments with lower I{sub c} values was presence of the Pb{sub 3}Sr{sub 2}Ca{sub 2}CuO{sub x} phase (Pb-3221). Microchemical analysis suggests that formation of this phase leads to variations in composition of Bi-2223 grains. As a result, the wires which exhibit the Pb-3221 phase consist of an assemblage of grains with a range of transition temperatures based on composition. Thus, in these segments, the current carrying capacity of individual grains at 77K varies from very good to poor, and a significant reduction in the overall I{sub c} of the segment is observed.
Date: November 1, 1993
Creator: Miller, D. J.; Hu, J. G.; Kostic, P.; Balachandran, U. & Haldar, P.
System: The UNT Digital Library
Collective acceleration in solar flares (open access)

Collective acceleration in solar flares

Solar flare data are examined with an eye to seeing if they suggest collective acceleration of ions. That, in fact, seems to be the case. The collective acceleration mechanism of Gershtein is reviewed and the possibilities of the mechanism are discussed.
Date: November 1, 1993
Creator: Barletta, W.; Sessler, A. M.; Xie, M.; Gershtein, S. S.; Krishan, V. & Reiser, M.
System: The UNT Digital Library