Direct Digital Phase Shift by DDS rf Source (open access)

Direct Digital Phase Shift by DDS rf Source

None
Date: April 13, 1993
Creator: A., Pei
Object Type: Report
System: The UNT Digital Library
Fiber optic chemical sensors for characterizing the carbon cycle in ocean margin regions (open access)

Fiber optic chemical sensors for characterizing the carbon cycle in ocean margin regions

The overall objective of our DOE-Ocean Margins Programs grant is to develop a pCO[sub 2] sensor for long-term monitoring of pCO[sub 2] in the ocean margins and to establish a proving ground for the development of other chemical sensors for characterizing the carbon cycle in these regions. We have succeeded in keeping with the approximate timeline outlined in the original proposal, which, for year 1 included the following objectives: Continue sensor optimization, test response characteristics (reagent and sample flow rates, temperature), introduce position sensitive photodiode and photodiode array spectrophotometers and evaluate, develop reliable and reproducible fabrication techniques, develop sensor based on preliminary studies optimized for field measurements (minimize size and power requirements), test long-term stability of the sensor in the laboratory, determine susceptibility to fouling and corrosion. This work is summarized below along with a brief review of the sensor's operating principle.
Date: April 13, 1993
Creator: DeGrandpre, Michael D. & Sayles, Frederick L.
Object Type: Report
System: The UNT Digital Library
Fiber optic chemical sensors for characterizing the carbon cycle in ocean margin regions. Annual progress report (open access)

Fiber optic chemical sensors for characterizing the carbon cycle in ocean margin regions. Annual progress report

The overall objective of our DOE-Ocean Margins Programs grant is to develop a pCO{sub 2} sensor for long-term monitoring of pCO{sub 2} in the ocean margins and to establish a proving ground for the development of other chemical sensors for characterizing the carbon cycle in these regions. We have succeeded in keeping with the approximate timeline outlined in the original proposal, which, for year 1 included the following objectives: Continue sensor optimization, test response characteristics (reagent and sample flow rates, temperature), introduce position sensitive photodiode and photodiode array spectrophotometers and evaluate, develop reliable and reproducible fabrication techniques, develop sensor based on preliminary studies optimized for field measurements (minimize size and power requirements), test long-term stability of the sensor in the laboratory, determine susceptibility to fouling and corrosion. This work is summarized below along with a brief review of the sensor`s operating principle.
Date: April 13, 1993
Creator: DeGrandpre, M. D. & Sayles, F. L.
Object Type: Report
System: The UNT Digital Library
Genetic algorithms for DNA sequence assembly (open access)

Genetic algorithms for DNA sequence assembly

This paper describes a genetic algorithm application to the DNA fragment assembly problems. The genetic algorithm uses a random key representation for representing the orderings of fragments. Two different fitness functions, both based on pairwise overlap strengths between fragments, were tested. The paper concludes that the genetic algorithm is a promising method for fragment assembly problems, achieving usable solutions quickly, but that the current fitness functions are flawed and that other representations might be more appropriate.
Date: April 13, 1993
Creator: Parsons, R.; Burks, C. (Los Alamos National Lab., NM (United States)) & Forrest, S. (New Mexico Univ., Albuquerque, NM (United States). Dept. of Computer Science)
Object Type: Article
System: The UNT Digital Library
Genetic algorithms for DNA sequence assembly (open access)

Genetic algorithms for DNA sequence assembly

This paper describes a genetic algorithm application to the DNA fragment assembly problems. The genetic algorithm uses a random key representation for representing the orderings of fragments. Two different fitness functions, both based on pairwise overlap strengths between fragments, were tested. The paper concludes that the genetic algorithm is a promising method for fragment assembly problems, achieving usable solutions quickly, but that the current fitness functions are flawed and that other representations might be more appropriate.
Date: April 13, 1993
Creator: Parsons, R.; Burks, C. & Forrest, S.
Object Type: Article
System: The UNT Digital Library
Numerically Controlled Phase Locked Loop Using Direct Digital Synthesizer (open access)

Numerically Controlled Phase Locked Loop Using Direct Digital Synthesizer

None
Date: April 13, 1993
Creator: A., Pei
Object Type: Report
System: The UNT Digital Library
Polar solvation and electron transfer (open access)

Polar solvation and electron transfer

The report is divided into the following sections: completion of previous studies on solvation dynamics, dipole lattice studies, inertial components of solvation response, simple models of solvation dynamics, rotational dynamics and dielectric friction, intramolecular electron transfer reactions, and intermolecular donor-acceptor complexes.
Date: April 13, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Polar Solvation and Electron Transfer. Annual Progress Report, July 1, 1992--June 30, 1993 (open access)

Polar Solvation and Electron Transfer. Annual Progress Report, July 1, 1992--June 30, 1993

The report is divided into the following sections: completion of previous studies on solvation dynamics, dipole lattice studies, inertial components of solvation response, simple models of solvation dynamics, rotational dynamics and dielectric friction, intramolecular electron transfer reactions, and intermolecular donor-acceptor complexes.
Date: April 13, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Burst mode FEL with the ETA-III induction linac (open access)

Burst mode FEL with the ETA-III induction linac

Pulses of 140 GHz microwaves have been produced at a 2 kHz rate using the ETA-III induction linac and IMP wiggler. The accelerator was run in bursts of up to 50 pulses at 6 MeV and greater than 2 kA peak current. A feedback timing control system was used to synchronize acceleration voltage pulses with the electron beam, resulting in sufficient reduction of the corkscrew and energy sweep for efficient FEL operation. Peak microwave power for short bursts was in the range 0.5--1.1 GW, which is comparable to the single-pulse peak power of 0.75--2 GW. FEL bursts of more than 25 pulses were obtained.
Date: May 13, 1993
Creator: Lasnier, C. J.; Allen, S. L. & Felker, B.
Object Type: Article
System: The UNT Digital Library
The development of coal-based technologies for Department of Defense facilities. Semiannual technical progress report, September 28, 1992--March 27, 1993 (open access)

The development of coal-based technologies for Department of Defense facilities. Semiannual technical progress report, September 28, 1992--March 27, 1993

The US Department of Defense (DOD), through an Interagency Agreement with the US Department of Energy (DOE), has initiated a three-phase program with the Consortium for Coal-Water Slurry Fuel Technology, with the aim of decreasing DOD`s reliance on imported oil by increasing its use of coal. The program is being conducted as a cooperative agreement between the Consortium and DOE and the first phase of the program is underway. Phase I activities are focused on developing clean, coal-based combustion technologies for the utilization of both micronized coal-water mixtures (MCWMs) and dry, micronized coal (MC) in fuel oil-designed industrial boilers. Phase II research and development activities will continue to focus on industrial boiler retrofit technologies by addressing emissions control and pre-combustion (i.e., slagging combustion and/or gasification) strategies for the utilization of high ash and high sulfur coals. Phase III activities will examine coal-based fuel combustion systems that cofire wastes. Each phase includes an engineering cost analysis and technology assessment. The activities and status of Phase I are described below. The objective in Phase I is to deliver fully engineered retrofit options for a fuel oil- designed watertube boiler located on a DOD installation to fire either MCWM or MC. This will …
Date: May 13, 1993
Creator: Miller, B. G.; Scaroni, A. W. & Hogg, R.
Object Type: Report
System: The UNT Digital Library
Elevation of surficial sediment/basalt contact in the Subsurface Disposal Area, Idaho National Engineering Laboratory (open access)

Elevation of surficial sediment/basalt contact in the Subsurface Disposal Area, Idaho National Engineering Laboratory

The elevation of the surficial sediment/basalt contact at the Subsurface Disposal Area (SDA), within the Radioactive Waste Management Complex (RWMC) is presented to provide a data base for future remedial actions at this site. About 1,300 elevation data from published and unpublished reports, maps, and surveyors notes were compiled to generate maps and cross-sections of the surficial sediment/basalt contact. In general, an east to west trending depression exists in the south central portion of the SDA with basalt closer to land surface on the northern and southern boundaries of the SDA. The lowest elevation of the surficial sediment/basalt contact is 4,979 ft and the greatest is land surface at 5,012 ft. The median elevation of the sediment/basalt interface is 4,994 ft. The median depth to basalt in the SDA is 16 ft if land surface elevation is assumed to be 5,010 ft. The depth from land surface to the sediment/basalt interface ranges from 24 ft in the southeast corner of the SDA to less than 3 ft at the north-central boundary of the SDA.
Date: May 13, 1993
Creator: Hubbell, J. M.
Object Type: Report
System: The UNT Digital Library
Mechanical degradation temperature of waste storage materials (open access)

Mechanical degradation temperature of waste storage materials

Heat loading analysis of the Solid Waste Disposal Facility (SWDF) waste storage configurations show the containers may exceed 90{degrees}C without any radioactive decay heat contribution. Contamination containment is primarily controlled in TRU waste packaging by using multiple bag layers of polyvinyl chloride and polyethylene. Since literature values indicate that these thermoplastic materials can begin mechanical degradation at 66{degrees}C, there was concern that the containment layers could be breached by heating. To better define the mechanical degradation temperature limits for the materials, a series of heating tests were conducted over a fifteen and thirty minute time interval. Samples of a low-density polyethylene (LDPE) bag, a high-density polyethylene (HDPE) high efficiency particulate air filter (HEPA) container, PVC bag and sealing tape were heated in a convection oven to temperatures ranging from 90 to 185{degrees}C. The following temperature limits are recommended for each of the tested materials: (1) low-density polyethylene -- 110{degrees}C; (2) polyvinyl chloride -- 130{degrees}C; (3) high-density polyethylene -- 140{degrees}C; (4) sealing tape -- 140{degrees}C. Testing with LDPE and PVC at temperatures ranging from 110 to 130{degrees}C for 60 and 120 minutes also showed no observable differences between the samples exposed at 15 and 30 minute intervals. Although these observed temperature …
Date: May 13, 1993
Creator: Fink, M. C. & Meyer, M. L.
Object Type: Report
System: The UNT Digital Library
Poroelasticity of rock (open access)

Poroelasticity of rock

Poroelasticity is the theoretical framework used to describe the coupled processes which occur when a fluid bearing porous material is deformed by a stress field. The theoretical basis for the treatment of problems in poroelasticity has been derived in an extensive body of work over the last fifty years, most notably by Biot. Many of Biot`s successors have attempted to find relationships between the physical properties of the material to be analyzed and the Biot coefficients. Our approach to this problem has both theoretical and experimental components. The general theoretical objective is to produce estimates of the Biot coefficients which are more realistic e.g.. are not limited by assumptions which preclude their use for real earth materials. Experiments are designed to measure the coefficients (or parameters which are directly related to them) which have not been measured as yet to provide new insight for improving the theory of poroelasticity. The experimental program is designed to determine the mechanical and transport properties of a well characterized set of synthetic and natural sandstones from static to ultrasonic frequencies.
Date: May 13, 1993
Creator: Bonner, B. P.; Berge, P. A.; Berryman, J. G. & Wang, H. F.
Object Type: Article
System: The UNT Digital Library
Refining a triangulation of a planar straight-line graph to eliminate large angles (open access)

Refining a triangulation of a planar straight-line graph to eliminate large angles

Triangulations without large angles have a number of applications in numerical analysis and computer graphics. In particular, the convergence of a finite element calculation depends on the largest angle of the triangulation. Also, the running time of a finite element calculation is dependent on the triangulation size, so having a triangulation with few Steiner points is also important. Bern, Dobkin and Eppstein pose as an open problem the existence of an algorithm to triangulate a planar straight-line graph (PSLG) without large angles using a polynomial number of Steiner points. We solve this problem by showing that any PSLG with {upsilon} vertices can be triangulated with no angle larger than 7{pi}/8 by adding O({upsilon}{sup 2}log {upsilon}) Steiner points in O({upsilon}{sup 2} log{sup 2} {upsilon}) time. We first triangulate the PSLG with an arbitrary constrained triangulation and then refine that triangulation by adding additional vertices and edges. Some PSLGs require {Omega}({upsilon}{sup 2}) Steiner points in any triangulation achieving any largest angle bound less than {pi}. Hence the number of Steiner points added by our algorithm is within a log {upsilon} factor of worst case optimal. We note that our refinement algorithm works on arbitrary triangulations: Given any triangulation, we show how to …
Date: May 13, 1993
Creator: Mitchell, S. A.
Object Type: Article
System: The UNT Digital Library
Study of Pu consumption in Advanced Light Water Reactors. Evaluation of GE Advanced Boiling Water Reactor plants (open access)

Study of Pu consumption in Advanced Light Water Reactors. Evaluation of GE Advanced Boiling Water Reactor plants

Timely disposal of the weapons plutonium is of paramount importance to permanently safeguarding this material. GE`s 1300 MWe Advanced Boiling Water Reactor (ABWR) has been designed to utilize fill] core loading of mixed uranium-plutonium oxide fuel. Because of its large core size, a single ABWR reactor is capable of disposing 100 metric tons of plutonium within 15 years of project inception in the spiking mode. The same amount of material could be disposed of in 25 years after the start of the project as spent fuel, again using a single reactor, while operating at 75 percent capacity factor. In either case, the design permits reuse of the stored spent fuel assemblies for electrical energy generation for the remaining life of the plant for another 40 years. Up to 40 percent of the initial plutonium can also be completely destroyed using ABWRS, without reprocessing, either by utilizing six ABWRs over 25 years or by expanding the disposition time to 60 years, the design life of the plants and using two ABWRS. More complete destruction would require the development and testing of a plutonium-base fuel with a non-fertile matrix for an ABWR or use of an Advanced Liquid Metal Reactor (ALMR). The …
Date: May 13, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Thermal and structural behavior of filters and windows for synchrotron x-ray sources (open access)

Thermal and structural behavior of filters and windows for synchrotron x-ray sources

This report contains the following discussions: Introduction: Use of filters and windows in the front end designs; An interactive code for 3D graphic viewing of absorbed power in filters/windows and a new heat load generation algorithm for the finite element analysis; Failure criteria and analysis methods for the filter and window assembly; Comparison with test data and existing devices in HASYLAB; Cooling the filter: Radiation cooling or conduction cooling?; Consideration of window and filter thickness: Thicker or thinner?; Material selection criteria for filters/windows; Photon transmission through filters/windows; Window and filter design for APS undulators; Window and filter design for APS wigglers; and Window design for APS bending magnet front ends.
Date: May 13, 1993
Creator: Wang, Z.; Hahn, U.; Dejus, R. & Kuzay, T.
Object Type: Report
System: The UNT Digital Library
Experience with performance based training of nuclear criticality safety engineers (open access)

Experience with performance based training of nuclear criticality safety engineers

For non-reactor nuclear facilities, the U.S. Department of Energy (DOE) does not require that nuclear criticality safety engineers demonstrate qualification for their job. It is likely, however, that more formalism will be required in the future. Current DOE requirements for those positions which do have to demonstrate qualification indicate that qualification should be achieved by using a systematic approach such as performance based training (PBT). Assuming that PBT would be an acceptable mechanism for nuclear criticality safety engineer training in a more formal environment, a site-specific analysis of the nuclear criticality safety engineer job was performed. Based on this analysis, classes are being developed and delivered to a target audience of newer nuclear criticality safety engineers. Because current interest is in developing training for selected aspects of the nuclear criticality safety engineer job, the analysis is incompletely developed in some areas.
Date: July 13, 1993
Creator: Taylor, R. G.
Object Type: Article
System: The UNT Digital Library
Fundamental mechanisms in flue gas conditioning. Quarterly report, April 1993--June 1993 (open access)

Fundamental mechanisms in flue gas conditioning. Quarterly report, April 1993--June 1993

The experiments we have been performing are primarily designed to define the extent to which water affects key properties of ashes, powders, and mixtures of sorbents and ashes. We have included selected data from prior quarterly reports in this report for the sake of completeness, and for comparisons with newly-acquired data. In several places in this report samples are referred to by their identification (SID) numbers. Table I provides a brief description of all the samples we have used in this project along with their SID numbers. As suggested by our literature review, our data indicate that water adsorption depends on particle morphology and surface chemistry. Our recent laboratory efforts were primarily directed toward the determination of the effects of adsorbed water on the tensile and cohesive strengths of powders, the development of apparatus for SO{sub 3} and organosiloxane conditioning, and the conditioning of powders and ashes with organosiloxane.
Date: July 13, 1993
Creator: Snyder, T. R.
Object Type: Report
System: The UNT Digital Library
Characterization of multiphase fluid flow during air-sparged hydrocyclone flotation by x-ray CT. Twelfth quarterly report, 14 May--13 August 1993 (open access)

Characterization of multiphase fluid flow during air-sparged hydrocyclone flotation by x-ray CT. Twelfth quarterly report, 14 May--13 August 1993

During this quarter some experiments from the previous set were repeated to check the reproducibility of the results. Also, a new set of experiments was carried out to study the effects of (1) collector dosage, (2) Q* -- the nondimensional ratio of air flow rate to slurry flow rate, and (3) slurry pressure on the flow characteristics. Four different Q* values with hydrophobic particles in the feed slurry were studied. The value of A*, the dimensionless ratio of overflow opening area to underflow opening area, was maintained at the same level (A* 1.00). Quartz particles of size {sup {minus}}100 {sup +}200 mesh were used for this study rather than coal particles because they did not abrade and were of a higher density. The reagents used were 40 ppM (water basis) of MIBC frother and 800 g of dodecyl amine collector per ton of dry solids in the suspension. In other experiments with no solids in the feed suspension, collector level in the water was varied at 0, 10 and 20 ppM. At room temperature, quartz is intrinsically hydrophilic while addition of the amine collector renders the quartz particles hydrophobic. The absence of collector will be referred to as the hydrophilic …
Date: August 13, 1993
Creator: Miller, J. D.
Object Type: Report
System: The UNT Digital Library
Development of measurement capabilities for the thermophysical properties of energy-related fluids. Annual report, December 1, 1992--November 30, 1993 (open access)

Development of measurement capabilities for the thermophysical properties of energy-related fluids. Annual report, December 1, 1992--November 30, 1993

The measurement capabilities to be developed include new apparatus for transport properties, thermodynamic properties, phase equilibria, and dielectric properties. Specific capabilities are: Thermal conductivity apparatus, vibrating wire viscometer, dual-sinker densimeter, high-temperature vibrating tube densimeter, dynamic phase equilibria apparatus, apparatus for dilute solutions, total-enthalpy flow calorimeter. Benchmark measurements were made (no data given) on pure and mixed alternative refrigerants and their mixtures with lubricants, and other fluids.
Date: August 13, 1993
Creator: Kayser, R. F.
Object Type: Report
System: The UNT Digital Library
Electric power monthly, August 1993 (open access)

Electric power monthly, August 1993

The Electric Power Monthly (EPM) presents monthly electricity statistics. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. The EPM is prepared by the Survey Management Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy. This publication provides monthly statistics at the US, Census division, and State levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions.
Date: August 13, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Flue gas conditioning for improved particle collection in electrostatic precipitators. Second topical report, Results of bench-scale screening of additives (open access)

Flue gas conditioning for improved particle collection in electrostatic precipitators. Second topical report, Results of bench-scale screening of additives

ADA Technologies, Inc. (ADA) has completed the bench-scale testing phase of a program to evaluate additives that will improve the collection of fine particles in electrostatic precipitators (ESPs). A bench-scale ESP was installed at the Consolidation Coal Company (CONSOL) combustion research and development facility in Library, PA in order to conduct the evaluation. During a two-week test, four candidate additives were injected into the flue gas ahead of a 100 acfm ESP to determine the effect on fly ash collectability. Two additives were found to reduce the emissions from the ESP. Additives ``C`` and ``D`` performed better than initially anticipated -- reducing emissions initially by 17%. Emissions were reduced by 27% after the ESP was modified by the installation of baffles to minimize sneakage. In addition to the measured improvements in performance, no detrimental effects (i.e., electrode fouling) were observed in the operation of the ESP during the testing. The measures of success identified for the bench-scale phase of the program have been surpassed. Since the additives will affect only non-rapping reentrainment particle losses, it is expected that an even greater improvement in particle collection will be observed in larger-scale ESPs. Therefore, positive results are anticipated during the pilot-scale phase …
Date: August 13, 1993
Creator: Durham, M. D.
Object Type: Report
System: The UNT Digital Library
High Luminosity p-p Operation at RHIC (open access)

High Luminosity p-p Operation at RHIC

None
Date: August 13, 1993
Creator: Harrison, M. A.
Object Type: Report
System: The UNT Digital Library
Stabilization of the external kink and other MHD issues. Summary report (open access)

Stabilization of the external kink and other MHD issues. Summary report

An MHD workshop entitled ``Stabilization of the External Kink and Other MHD Issues`` was held June 1993. This is a summary report of activities at that workshop, structured to respond to the three questions in the charge (letter from J. Willis). The experimental and theoretical status of these issues, and the R&D needs in each area, are addressed. We discuss the potential impact on the TPX and ITER programs of these issues. The workshop participants came from a broad and diverse range of institutions in the fusion program, including international participants. As a result, we believe the summary here reflects some consensus of the community on these very important program issues, and that the TPX and ITER programs will benefit from these discussions. The title of the workshop was chosen to indicate both our knowledge and our uncertainty of MHD phenomena limiting {beta} and causing disruptions in tokamaks. The purpose was to bring together theorists and experimentalist in order to assess our current understanding of the external kink instability at high {beta}, and to assess the potential for passive or active stabilization of the dominant modes. We also outlined the R&D needed for TPX and other future devices. Not only …
Date: August 13, 1993
Creator: Freidberg, J. P.; Goldston, R. J.; Jardin, S. C.; Neilson, G. H.; Rosenbluth, M. N.; Taylor, T. S. et al.
Object Type: Article
System: The UNT Digital Library