Aerial thermography studies of power plant heated lakes (open access)

Aerial thermography studies of power plant heated lakes

Remote sensing temperature measurements of water bodies is complicated by the temperature differences between the true surface or skin water and the bulk water below. Weather conditions control the reduction of the skin temperature relative to the bulk water temperature. Typical skin temperature depressions range from a few tenths of a degree Celsius to more than one degree. In this research project, the Savannah River Technology Center (SRTC) used aerial thermography and surface-based meteorological and water temperature measurements to study a power plant cooling lake in South Carolina. Skin and bulk water temperatures were measured simultaneously for imagery calibration and to produce a database for modeling of skin temperature depressions as a function of weather and bulk water temperatures. This paper will present imagery that illustrates how the skin temperature depression was affected by different conditions in several locations on the lake and will present skin temperature modeling results.
Date: January 26, 2000
Creator: Villa-Aleman, E.
System: The UNT Digital Library
The B {r{underscore}arrow} D*{ell}{nu} form factor at zero recoil (open access)

The B {r{underscore}arrow} D*{ell}{nu} form factor at zero recoil

The authors describe a model independent lattice QCD method for determining the deviation from unity for h{sub A{sub 1}}, the B {r{underscore}arrow} D*{ell}{nu} form factor at zero recoil. They extend the double ratio method previously used to determine the B {r{underscore}arrow} D{ell}{nu} form factor. The bulk of statistical and systematic errors cancel in the double ratios they consider, yielding form factors which promise to reduce present theoretical uncertainties in the determination of {vert{underscore}bar}V{sub cb}{vert{underscore}bar}. They present results from a prototype calculation at a single lattice spacing corresponding to {beta} = 5.7.
Date: January 26, 2000
Creator: Simone, J. N.; Hashimoto, S.; El-Khadra, A. X.; Kronfeld, A. S.; Mackenzie, P. B. & Ryan, S. M.
System: The UNT Digital Library
Characterization of and waste acceptance radionuclide to be reported for the 2nd macro-batch of high-level waste sludge being vitrified in the DWPF melter (open access)

Characterization of and waste acceptance radionuclide to be reported for the 2nd macro-batch of high-level waste sludge being vitrified in the DWPF melter

The Defense Waste Processing Facility (DWPF), at the Savannah River Site (SRS), is currently processing the second million gallon batch (Macro-Batch 2) of radioactive sludge slurry into a durable borosilicate glass for permanent geological disposal. To meet the reporting requirements as specified in the Department of Energy's Waste Acceptance Product Specifications (WAPS), for the final glass product, the nonradioactive and radioactive compositions must be provided for a Macro-Batch of material. In order to meet this requirement, sludge slurry samples from Macro-Batch 2 were analyzed in the Shielded Cells Facility of the Savannah River Technology Center (SRTC). This information is used to complete the necessary Production Records at DWPF so that the final glass product, resulting from Macro Batch 2, may be disposed of at a Federal Repository. This paper describes the results obtained from the analyses of the sludge slurry samples taken from Macro-Batch 2 to meet the reporting requirements of the WAPS. Twenty eight elements were identified for the nonradioactive composition and thirty one for the radioactive composition. The reportable radioisotopes range from C-14 to Cm-246.
Date: January 26, 2000
Creator: Fellinger, T. L.
System: The UNT Digital Library
Characterization of melt-infiltrated SiC/SiC composite combustor liners using meso- and micro-NDE techniques (open access)

Characterization of melt-infiltrated SiC/SiC composite combustor liners using meso- and micro-NDE techniques

Melt-infiltrated ceramic matrix composite SiC/SiC material systems are under development for use in combustor liners for low-emission advanced gas turbines. Uncertainty in repeatability of processing methods for these large components (33--76 cm diameter), and hence possible reduced reliability for the end user. This requires that appropriate test methods, at both meso- and micro-scale, be used to ensure that the liners are acceptable for use. Nondestructive evaluation (NDE) methods, if demonstrated to reliably detect changes caused by processing, would be of significant benefit to both manufacturer and end user. This paper describes the NDE methods and their applications in detecting a process upset in a melt-infiltrated 33 cm combustor liner and how high-resolution scanning electron microscopy was used to verify the NDE data.
Date: January 26, 2000
Creator: Ellingson, W. A.; Sun, J. G.; More, K. L. & Hines, R.
System: The UNT Digital Library
Chemical Vapor Deposition of Fluoroalkylsilane Monolayer Films for Adhesion Control in Microelectromechanical Systems (open access)

Chemical Vapor Deposition of Fluoroalkylsilane Monolayer Films for Adhesion Control in Microelectromechanical Systems

We have developed a new process for applying a hydrophobic, low adhesion energy coating to microelectromechanical (MEMS) devices. Monolayer films are synthesized from tridecafluoro-1,1,2,2-tetrahydrooctyltrichlorosilane (FOTS) and water vapor in a low-pressure chemical vapor deposition process at room temperature. Film thickness is self-limiting by virtue of the inability of precursors to stick to the fluorocarbon surface of the film once it has formed. We have measured film densities of {approx}3 molecules nm{sup 2} and film thickness of {approx}1 nm. Films are hydrophobic, with a water contact angle >110{sup o}. We have also incorporated an in-situ downstream microwave plasma cleaning process, which provides a clean, reproducible oxide surface prior to film deposition. Adhesion tests on coated and uncoated MEMS test structures demonstrate superior performance of the FOTS coatings. Cleaned, uncoated cantilever beam structures exhibit high adhesion energies in a high humidity environment. An adhesion energy of 100 mJ m{sup -2} is observed after exposure to >90% relative humidity. Fluoroalkylsilane coated beams exhibit negligible adhesion at low humidity and {<=} 20 {micro}J m{sup -2} adhesion energy at >90% relative humidity. No obvious film degradation was observed for films exposed to >90% relative humidity at room temperature for >24 hr.
Date: January 26, 2000
Creator: MAYER,THOMAS M.; DE BOER,MAARTEN P.; SHINN,NEAL D.; CLEWS,PEGGY J. & MICHALSKE,TERRY A.
System: The UNT Digital Library
Correction of high gradient quadrupole harmonics with magnetic shims (open access)

Correction of high gradient quadrupole harmonics with magnetic shims

Superconducting quadrupole magnets with 70 mm aperture and nominal field gradient of 215 T/m are being developed by the US-LHC Accelerator Project for the Interaction Regions of the Large Hadron Collider. Due to large beam size and orbit displacement in the final focusing triplet, these magnets are subject to stringent field quality requirements. For this reason, a correction scheme based on magnetic shims was investigated. This paper reports design calculations, fabrication issues and tests results involving magnetic shims.
Date: January 26, 2000
Creator: Sabbi, G.
System: The UNT Digital Library
Coupling Automated Electron Backscatter Diffraction with Transmission Electron and Atomic Force Microscopies (open access)

Coupling Automated Electron Backscatter Diffraction with Transmission Electron and Atomic Force Microscopies

Grain boundary network engineering is an emerging field that encompasses the concept that modifications to conventional thermomechanical processing can result in improved properties through the disruption of the random grain boundary network. Various researchers have reported a correlation between the grain boundary character distribution (defined as the fractions of special and random grain boundaries) and dramatic improvements in properties such as corrosion and stress corrosion cracking, creep, etc. While much early work in the field emphasized property improvements, the opportunity now exists to elucidate the underlying materials science of grain boundary network engineering. Recent investigations at LLNL have coupled automated electron backscatter diffraction (EBSD) with transmission electron microscopy (TEM) and atomic force microscopy (AFM) to elucidate these fundamental mechanisms. This investigation provides evidence that grain boundary network engineering and the formation of annealing twins disrupt the connectivity of the random grain boundary network and is likely responsible for the experimentally observed improvement in properties. This work illustrates that coupling of automated EBSD with other microstructural probes such as TEM and AFM provides data of greater value than any single technique in isolation. The coupled techniques have been applied to aid in understanding the underlying mechanisms of grain boundary network engineering …
Date: January 26, 2000
Creator: Schwartz, A.J.; Kumar, M.; Bedrossian, P.J. & King, W.E.
System: The UNT Digital Library
Development and testing of insulated drillpipe (open access)

Development and testing of insulated drillpipe

The Geothermal Research Department at Sandia National Laboratories, in collaboration with Drill Cool Systems, Inc., has worked to develop and test insulated drillpipe (IDP). IDP will allow much cooler drilling fluid to reach the bottom of the hole, making possible the use of downhole motors, electronics, and steering tools that are now unusable in high-temperature formations. Other advantages of cooler fluid include reduced degradation of drilling fluid, longer bit life, and reduced corrosion rates. The paper describes the theoretical background, laboratory testing, and field testing of IDP. Structural and thermal laboratory testing procedures and results are described. Results are given for a field test in a geothermal well, in which circulating temperatures in IDP are compared with those in conventional drillpipe (CDP) at different flow rates. A brief description of the software used to model wellbore temperature and to calculate sensitivity to IDP design differences is included, along with a comparison of calculated and measured wellbore temperatures in the field test. Analysis of mixed (IDP and CDP) drill strings and discussion of where IDP should be placed in a mixed string are presented.
Date: January 26, 2000
Creator: FINGER,JOHN T.; JACOBSON,RONALD D. & CHAMPNESS,A.T.
System: The UNT Digital Library
Diagnostics-while drilling: Reducing the cost of geothermal-produced electricity (open access)

Diagnostics-while drilling: Reducing the cost of geothermal-produced electricity

The goal of this document is to estimate the potential impact of proposed new Diagnostics-While-Drilling technology on the cost of electricity (COE) produced with geothermal energy. A cost model that predicts the COE was developed and exercised over the range of conditions found for geothermal plants in flashed-steam, binary, and enhanced-reservoir (e.g., Hot Dry Rock) applications. The calculations were repeated assuming that DWD technology is available to reduce well costs and improve well productivity. The results indicate that DWD technology would reduce the geothermal COE by 2--31%, depending on well depth, well productivity, and the type of geothermal reservoir. For instance, for a typical 50-MW, flashed-steam geothermal power plant employing 3-MW wells, 6,000-ft deep, the model predicts an electricity cost of 4.9 cents/kwh. With the DWD technology envisioned, the electricity cost could be reduced by nearly 20%, to less than 4 cents/kwh. Such a reduction in the cost of electricity would give geothermal power a competitive edge over other types of power at many locations across the US and around the world. It is thus believed that DWD technology could significantly expand the role of geothermal energy in providing efficient, environment-friendly electric generating capacity.
Date: January 26, 2000
Creator: PRAIRIE,MICHAEL R. & GLOWKA,DAVID A.
System: The UNT Digital Library
The effect of adding crystalline silicotitanate on the durability, liquidus, and viscosity of simulated high-level waste glasses at Savannah River Site (open access)

The effect of adding crystalline silicotitanate on the durability, liquidus, and viscosity of simulated high-level waste glasses at Savannah River Site

This report provides a summary of the results obtained for a limited variability study for glasses containing Crystalline Silicotitanate (CST), Monosodium Titanate (MST), and either simulated Purex or HM sludge. Twenty-two glasses containing Purex sludge and three glasses containing HM sludge were fabricated and tested. The fabricated glasses were tested for durability using the 7-day Product Consistency Test (PCT) and characterized by measuring the viscosity at 1,150 C and by determining an approximate, bounding liquidus temperature. The current models used by Defense Waste Processing Facility (DWPF) for predicting durability, viscosity, and liquidus temperature were applied to all 25 glasses. The goal of this work was to identify any major problems from a glass perspective, within the scope of this effort, which could potentially preclude the use of CST at DWPF.
Date: January 26, 2000
Creator: Harbour, J.R.
System: The UNT Digital Library
Effect of defects on the critical points in YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} (open access)

Effect of defects on the critical points in YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}}

The upper and lower critical points are investigated in untwinned YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} single crystals with dilute columnar defects. Dilute columnar defects raise the upper critical point, indicating that the transition near the upper critical point is a vortex entanglement transition. The lower critical point is very sensitive to columnar defect disorder and its position can be described by a Lindemann-like criterion similar to that for melting. Dilute columnar defects induce non-linear behavior in the I-V curves of the vortex liquid state above the lower critical point, which the authors interpret as a vestige of the critical region associated with the Bose glass transition below the lower critical point.
Date: January 26, 2000
Creator: Kwok, W. K.; Olsson, R. J.; Karapetrov, G.; Paulis, L. M.; Moulton, W. G.; Hofman, D. J. et al.
System: The UNT Digital Library
Foam testing of an alternative antifoam agent for the processing of radioactive sludge in the Defense Waste Processing Facility (open access)

Foam testing of an alternative antifoam agent for the processing of radioactive sludge in the Defense Waste Processing Facility

The Defense Waste Processing Facility (DWPF) at the Savannah River Site is responsible for immobilizing high level radioactive waste (HLW) as glass-filled steel canisters for permanent storage. In the DWPF facility, the HLW sludge undergoes chemical treatment to prepare it for vitrification in a melter. The generation of stable foams is possible during treatment. The current DWPF antifoam is ineffective in preventing and minimizing the formation of foam. The adverse consequences of excess foam can be severe enough to cause foam to exit the evaporator and collect in the condensate. A foamover will contaminate the relatively clean condensate with HLW solids. It can also potentially lead to the production of an unsuitable melter feed that would not make quality glass. Both of these consequences are costly and time consuming to correct. A new antifoam agent was developed by the Illinois Institute of Technology, IIT, for DWPF in an attempt to minimize or eliminate the frequency of these foamovers. This antifoam agent was demonstrated to be superior to the existing DWPF antifoam agent in laboratory scale experiments. However, the DWPF evaporation heat flux was not achievable in the laboratory scale equipment. A 1/240th-scale pilot facility was built to achieve this heat …
Date: January 26, 2000
Creator: Koopman, D. C.
System: The UNT Digital Library
Implementing the Corrective Action Management Unit at Sandia National Laboratories, New Mexico (open access)

Implementing the Corrective Action Management Unit at Sandia National Laboratories, New Mexico

In September 1997, following significant public and regulator interaction, Sandia Corporation (Sandia) was granted a Resource Conservation and Recovery Act (RCRA) and Hazardous Solid Waste Amendment (HSWA) permit modification allowing construction and operation of a Correction Action Management Unit (CAMU). The CAMU follows recent regulatory guidance that allows for cost-effective, expedient cleanup of contaminated sites and management of hazardous remediation wastes. The CAMU was designed to store, treat, and provide long-term management for Environmental Restoration (ER) derived wastes. The 154 square meter CAMU site at Sandia National Laboratories, New Mexico (SNL/NM), includes facilities for storing bulk soils and containerized wastes, for treatment of bulk soils, and has a containment cell for long-term disposition of waste. Proposed treatment operations include soil washing and low temperature thermal desorption. The first waste was accepted into the CAMU for temporary storage in January 1999. Construction at the CAMU was completed in March 1999, and baseline monitoring of the containment cell has commenced. At completion of operations the facility will be closed, the waste containment cell will be covered, and long-term post-closure monitoring will begin. Sandia's CAMU is the only such facility within the US Department of Energy (DOE) complex. Implementing this innovative approach to …
Date: January 26, 2000
Creator: Moore, Darlene R.; Schrader, Scott A.; King, Gabriel G. & Cormier, John
System: The UNT Digital Library
Lead zirconate titanate on base metal foils: An approach for embedded high-K passive components (open access)

Lead zirconate titanate on base metal foils: An approach for embedded high-K passive components

An approach for embedding high-K dielectric thin films into polymer packages has been developed. Pb{sub 0.85}La{sub 0.15}(Zr{sub 0.52}Ti{sub 0.48}){sub 0.96}O{sub 3} thin films were prepared by chemical solution deposition on 50 {micro}m thick Ni-coated Cu foils. Sputter deposited Ni top electrodes completed the all base-metal capacitor stack. After high temperature N{sub 2} crystallization anneals, the PLZT composition showed reduction resistance while the base-metal foils remained flexible. Capacitance density and Loss tangent values range between 300 and 400 nF/cm{sup 2} and 0.01 and 0.02 from 1 to 1,000 kHz respectively. These properties represent a 2 to 3 order of magnitude improvement over available embedded capacitor technologies for polymeric packages.
Date: January 26, 2000
Creator: Maria, J. P.; Cheek, K.; Streiffer, S. K.; Kim, S. H.; Dunn, G. & Kingon, A. I.
System: The UNT Digital Library
Mechanical design and analysis of the Fermilab 11 T Nb{sub 3}Sn dipole model (open access)

Mechanical design and analysis of the Fermilab 11 T Nb{sub 3}Sn dipole model

The goal of the Fermilab High Field Magnet (HFM) R and D project is to explore various designs and production technology of a high-field, low-cost Nb{sub 3}Sn accelerator magnet suitable for a future Very Large Hadron Collider (VLHC). The model under fabrication consists of two-layer shell-type coil with 43.5 mm aperture and cold iron yoke. Fermilab concept of magnet design and fabrication technology involves some specific features such as curing of half-coil with ceramic binder/matrix before reaction, and then simultaneous reaction and impregnation of both half-coils to get a coil pipe structure. The coil pipe is mechanically supported by the vertically-split iron yoke locked by two aluminum clamps and a thick stainless steel skin. 2D finite element analysis has been performed to study and optimize the prestress in the coil and in the structural elements at room temperature and at 4.2 K. Model description, material properties and the results of mechanical analysis are reported in this paper.
Date: January 26, 2000
Creator: Ambrosio, G.
System: The UNT Digital Library
Muon Collider/Neutrino Factory: Status and prospects (open access)

Muon Collider/Neutrino Factory: Status and prospects

During the 1990s an international collaboration has been studying the possibility of constructing and operating a high-energy high-luminosity {mu}{sup +}{mu}{sup {minus}} collider. Such a machine could be the approach of choice to extend the discovery reach beyond that of the LHC. More recently, a growing collaboration is exploring the potential of a stored-muon-beam neutrino factory to elucidate neutrino oscillations. A neutrino factory could be an attractive stepping-stone to a muon collider. Its construction, possibly feasible within the coming decade, could have substantial impact on neutrino physics.
Date: January 26, 2000
Creator: Kaplan, D. M.
System: The UNT Digital Library
New prediction-augmented classical least squares (PACLS) methods: Application to unmodeled interferents (open access)

New prediction-augmented classical least squares (PACLS) methods: Application to unmodeled interferents

A significant improvement to the classical least squares (CLS) multivariate analysis method has been developed. The new method, called prediction-augmented classical least squares (PACLS), removes the restriction for CLS that all interfering spectral species must be known and their concentrations included during the calibration. The authors demonstrate that PACLS can correct inadequate CLS models if spectral components left out of the calibration can be identified and if their spectral shapes can be derived and added during a PACLS prediction step. The new PACLS method is demonstrated for a system of dilute aqueous solutions containing urea, creatinine, and NaCl analytes with and without temperature variations. The authors demonstrate that if CLS calibrations are performed using only a single analyte's concentration, then there is little, if any, prediction ability. However, if pure-component spectra of analytes left out of the calibration are independently obtained and added during PACLS prediction, then the CLS prediction ability is corrected and predictions become comparable to that of a CLS calibration that contains all analyte concentrations. It is also demonstrated that constant-temperature CLS models can be used to predict variable-temperature data by employing the PACLS method augmented by the spectral shape of a temperature change of the water …
Date: January 26, 2000
Creator: HAALAND,DAVID M. & MELGAARD,DAVID K.
System: The UNT Digital Library
Process maps for plasma spray: Part 1: Plasma-particle interactions (open access)

Process maps for plasma spray: Part 1: Plasma-particle interactions

This is the first paper of a two part series based on an integrated study carried out at Sandia National Laboratories and the State University of New York at Stony Brook. The aim of the study is to develop a more fundamental understanding of plasma-particle interactions, droplet-substrate interactions, deposit formation dynamics and microstructural development as well as final deposit properties. The purpose is to create models that can be used to link processing to performance. Process maps have been developed for air plasma spray of molybdenum. Experimental work was done to investigate the importance of such spray parameters as gun current, auxiliary gas flow, and powder carrier gas flow. In-flight particle diameters, temperatures, and velocities were measured in various areas of the spray plume. Samples were produced for analysis of microstructures and properties. An empirical model was developed, relating the input parameters to the in-flight particle characteristics. Multi-dimensional numerical simulations of the plasma gas flow field and in-flight particles under different operating conditions were also performed. In addition to the parameters which were experimentally investigated, the effect of particle injection velocity was also considered. The simulation results were found to be in good general agreement with the experimental data.
Date: January 26, 2000
Creator: Gilmore, Delwyn L.; Neiser, Richard A., Jr.; Wan, Yuepeng & Sampath, Sanjay
System: The UNT Digital Library
Processing and mechanical properties of silicon nitride formed by robocasting aqueous slurries (open access)

Processing and mechanical properties of silicon nitride formed by robocasting aqueous slurries

Robocasting is a new freeform fabrication technique for dense ceramics. It uses robotics to control deposition of ceramic slurries through an orifice. The optimization of concentrated aqueous Si{sub 3}N{sub 4} slurry properties to achieve high green density robocast bodies and subsequent high sintered densities was investigated. The effects of pH, electrolyte, additives and solids loading on the dispersion and rheological properties of Si{sub 3}N{sub 4} slurries were determined. The mechanical behavior of sintered robocast bars was determined and compared to conventionally produced silicon nitride ceramics.
Date: January 26, 2000
Creator: He, Guoping; Hirschfeld, Deidre A. & Cesarano, Joseph, III
System: The UNT Digital Library
Reaction engineering of co-condensing (methyl)ethoxysilane mixtures: Kinetic characterization and modeling (open access)

Reaction engineering of co-condensing (methyl)ethoxysilane mixtures: Kinetic characterization and modeling

Molecular homogeneity frequently plays a decisive role in the effective application of organically modified silicate copolymers. However, methods of directly characterizing copolymerization extent in siloxanes generated from mixed alkoxysilanes are not always available or convenient. The authors present an alternative tool for determining kinetic parameters for models of alkoxysilane hydrolytic copolycondensation. Rather than restricting attention to single step batch reactors, they use a semibatch reactor with varying time of injection of one component. They describe the fitting method and show that all necessary kinetic parameters can be determined from a series of ordinary {sup 29}Si NMR data in a straightforward case study: copolymerization of dimethyldiethoxy silane and trimethylethoxysilane. Under conditions providing no direct {sup 29}Si NMR signature of copolymerization, they find kinetic trends consistent with those previously reported. As further validation, the results of a new series of experiments (varying the ratio of mono-functional to difunctional monomer) are predicted by the semibatch copolymerization model and measured parameters. Based on these results, they are able to calculate the molecular homogeneity in the copolymer products investigated. Even for this relatively simple system, the optimal injection time is a complex function of residence time, but early injection of the faster-condensing monomer gives the …
Date: January 26, 2000
Creator: Rankin, Stephen E. & McCormick, Alon V.
System: The UNT Digital Library
Recent results and perspectives at CDF and D0 (open access)

Recent results and perspectives at CDF and D0

Over the course of the past years the experimental measurements performed by the two large collaborations, CDF and D0, at the Fermilab Tevatron Collider have fueled advances in the understanding of physics at the energy frontier. At the present time the accelerator complex and the two detectors are undergoing substantial improvements. In this paper, they provide a discussion of some recent results which in turn provides a framework within which one can look to future prospects.
Date: January 26, 2000
Creator: Montgomery, H.E.
System: The UNT Digital Library
Requirements assessment and operational demands for a resource mapping rover mission to the lunar polar regions (open access)

Requirements assessment and operational demands for a resource mapping rover mission to the lunar polar regions

A preliminary set of requirements for a robotic rover mission to the lunar polar region are described and assessed. Tasks to be performed by the rover include core drill sample acquisition, mineral and volatile soil content assay, and significant wide area traversals. Assessment of the postulated requirements is performed using first order estimates of energy, power, and communications throughput issues. Two potential rover system configurations are considered, a smaller rover envisioned as part of a group of multiple rovers, and a larger single rover envisioned along more traditional planetary surface rover concept lines.
Date: January 26, 2000
Creator: KLARER,PAUL R.; BINDER,ALAN B. & LENARD,ROGER X.
System: The UNT Digital Library
Study of the react and wind technique for a Nb{sub 3}Sn common coil dipole (open access)

Study of the react and wind technique for a Nb{sub 3}Sn common coil dipole

Fermilab, in collaboration with LBNL, is exploring the use of the react and wind technique for a common coil dipole with a Nb{sub 3}Sn Rutherford cable. An R and D program on conductor design and magnet technology was begun aiming at an 11 T, 2 layer, 30 mm aperture design operating at 4.5 K. The goal is to explore the feasibility of the react and wind technique for flat coils with a minimum bending radius of 90 mm. In order to improve the understanding of the I{sub c} degradation caused by bending after reaction this effect will be studied on both strands and cables. In this paper, the authors present two techniques to measure the critical current degradation due to bending, both in wires and cables, using standard test facilities. Together with the description of the program they show the results of the first measurements on strands and the layout of the cables that are being produced.
Date: January 26, 2000
Creator: Ambrosio, G.
System: The UNT Digital Library
Synthesis of logic circuits with evolutionary algorithms (open access)

Synthesis of logic circuits with evolutionary algorithms

In the last decade there has been interest and research in the area of designing circuits with genetic algorithms, evolutionary algorithms, and genetic programming. However, the ability to design circuits of the size and complexity required by modern engineering design problems, simply by specifying required outputs for given inputs has as yet eluded researchers. This paper describes current research in the area of designing logic circuits using an evolutionary algorithm. The goal of the research is to improve the effectiveness of this method and make it a practical aid for design engineers. A novel method of implementing the algorithm is introduced, and results are presented for various multiprocessing systems. In addition to evolving standard arithmetic circuits, work in the area of evolving circuits that perform digital signal processing tasks is described.
Date: January 26, 2000
Creator: JONES,JAKE S. & DAVIDSON,GEORGE S.
System: The UNT Digital Library