Information, complexity and efficiency: The automobile model (open access)

Information, complexity and efficiency: The automobile model

The new, rapidly evolving field of industrial ecology - the objective, multidisciplinary study of industrial and economic systems and their linkages with fundamental natural systems - provides strong ground for believing that a more environmentally and economically efficient economy will be more information intensive and complex. Information and intellectual capital will be substituted for the more traditional inputs of materials and energy in producing a desirable, yet sustainable, quality of life. While at this point this remains a strong hypothesis, the evolution of the automobile industry can be used to illustrate how such substitution may, in fact, already be occurring in an environmentally and economically critical sector.
Date: August 8, 1996
Creator: Allenby, B.
Object Type: Article
System: The UNT Digital Library
Nuclear fuels technologies fiscal year 1996 research and research development test results (open access)

Nuclear fuels technologies fiscal year 1996 research and research development test results

During fiscal year 1996, the Department of Energy`s Office of Fissile Materials Disposition (OFMD) funded Los Alamos National Laboratory (LANL) to investigate issues associated with the fabrication of plutonium from dismantled weapons into mixed-oxide (MOX) nuclear fuel for disposition in nuclear power reactors. These issues can be divided into two main categories: issues associated with the fact that the plutonium from dismantled weapons contains gallium, and issues associated with the unique characteristics of the PuO{sub 2} produced by the dry conversion process that OFMD is proposing to convert the weapons material. Initial descriptions of the experimental work performed in fiscal year 1996 to address these issues can be found in Nuclear Fuels Technologies Fiscal Year 1996 Research and Development Test Matrices`. However, in some instances the change in programmatic emphasis towards the Parallex program either altered the manner in which some of these experiments were performed (i.e., the work was done as part of the Parallex fabrication development and not as individual separate-effects tests as originally envisioned) or delayed the experiments into Fiscal Year 1997. This report reviews the experiments that were conducted and presents the results. 7 figs., 14 tabs.
Date: November 8, 1996
Creator: Beard, C. A.; Blair, H. T.; Buksa, J. J. & Butt, D. P.
Object Type: Report
System: The UNT Digital Library
Tank characterization report for double-shell tank 241-AN-101 (open access)

Tank characterization report for double-shell tank 241-AN-101

This document summarizes the information on the historical uses, present status, and the sampling and analysis results of waste stored in Tank 241-AN-101. This report supports the requirements of Tri-Party Agreement Milestone M-44-09.
Date: August 8, 1996
Creator: Benar, C. J.
Object Type: Report
System: The UNT Digital Library
Shake table testing of structural clay tile infilled frames (open access)

Shake table testing of structural clay tile infilled frames

Two steel frames with structural clay tile infills were tested under simulated seismic loads in both the out-of-plane and in-plane direction. Out-of-plane testing showed that infill panels separate from their bounding frame, and respond at their own natural frequency during a seismic excitation. Due to arching, the panels remain stable. In-plane seismic testing showed similar behavior patterns to previous static testing. The natural frequency was adequately predicted using a piecewise linear equivalent strut analytical method. The structure was then subjected to over one thousand cycles of loading using a sine sweep before failure.
Date: March 8, 1996
Creator: Bennett, R. M.; Fowler, J. J. & Flanagan, R. D.
Object Type: Report
System: The UNT Digital Library
Low-level wastewater treatment facility process control operational test report (open access)

Low-level wastewater treatment facility process control operational test report

This test report documents the results obtained while conducting operational testing of a new TK 102 level controller and total outflow integrator added to the NHCON software that controls the Low-Level Wastewater Treatment Facility (LLWTF). The test was performed with WHC-SD-CP-OTP 154, PFP Low-Level Wastewater Treatment Facility Process Control Operational Test. A complete test copy is included in appendix A. The new TK 102 level controller provides a signal, hereafter referred to its cascade mode, to the treatment train flow controller which enables the water treatment process to run for long periods without continuous operator monitoring. The test successfully demonstrated the functionality of the new controller under standard and abnormal conditions expected from the LLWTF operation. In addition, a flow totalizer is now displayed on the LLWTF outlet MICON screen which tallies the process output in gallons. This feature substantially improves the ability to retrieve daily process volumes for maintaining accurate material balances.
Date: April 8, 1996
Creator: Bergquist, G. G.
Object Type: Report
System: The UNT Digital Library
Conceptual design for a user-friendly adaptive optics system at Lick Observatory (open access)

Conceptual design for a user-friendly adaptive optics system at Lick Observatory

In this paper, we present a conceptual design for a general-purpose adaptive optics system, usable with all Cassegrain facility instruments on the 3 meter Shane telescope at the University of California`s Lick Observatory located on Mt. Hamilton near San Jose, California. The overall design goal for this system is to take the sodium-layer laser guide star adaptive optics technology out of the demonstration stage and to build a user-friendly astronomical tool. The emphasis will be on ease of calibration, improved stability and operational simplicity in order to allow the system to be run routinely by observatory staff. A prototype adaptive optics system and a 20 watt sodium-layer laser guide star system have already been built at Lawrence Livermore National Laboratory for use at Lick Observatory. The design presented in this paper is for a next- generation adaptive optics system that extends the capabilities of the prototype system into the visible with more degrees of freedom. When coupled with a laser guide star system that is upgraded to a power matching the new adaptive optics system, the combined system will produce diffraction-limited images for near-IR cameras. Atmospheric correction at wavelengths of 0.6-1 mm will significantly increase the throughput of the most …
Date: March 8, 1996
Creator: Bissinger, H.D.; Olivier, S. & Max, C.
Object Type: Article
System: The UNT Digital Library
Keck adaptive optics: control subsystem (open access)

Keck adaptive optics: control subsystem

Adaptive optics on the Keck 10 meter telescope will provide an unprecedented level of capability in high resolution ground based astronomical imaging. The system is designed to provide near diffraction limited imaging performance with Strehl {gt} 0.3 n median Keck seeing of r0 = 25 cm, T =10 msec at 500 nm wavelength. The system will be equipped with a 20 watt sodium laser guide star to provide nearly full sky coverage. The wavefront control subsystem is responsible for wavefront sensing and the control of the tip-tilt and deformable mirrors which actively correct atmospheric turbulence. The spatial sampling interval for the wavefront sensor and deformable mirror is de=0.56 m which gives us 349 actuators and 244 subapertures. This paper summarizes the wavefront control system and discusses particular issues in designing a wavefront controller for the Keck telescope.
Date: March 8, 1996
Creator: Brase, J.M.; An, J. & Avicola, K.
Object Type: Article
System: The UNT Digital Library
Prototype development and testing of ultrafine grain NZP ceramics. Quarterly technical progress report No. 3, October 28, 1995--January 27, 1996 (open access)

Prototype development and testing of ultrafine grain NZP ceramics. Quarterly technical progress report No. 3, October 28, 1995--January 27, 1996

Caterpillar has been developing advanced low-heat-rejection (LHR) engine designs because by insulating the combustion chamber components for reduced heat rejection, improved fuel economy and emission reduction can be achieved. The insulation eliminates heat loss during the closed portion of the cycle and increases the combustion temperature. Increased combustion temperatures improve emissions by reducing the amount of particulate or smoke. The higher combustion temperatures also provide additional energy to drive a turbocharger that, in turn, improves the overall efficiency of the engine system and results in increased fuel economy.
Date: February 8, 1996
Creator: Brown, J. J.
Object Type: Report
System: The UNT Digital Library
Gist: A scientific graphics package for Python (open access)

Gist: A scientific graphics package for Python

{open_quotes}Gist{close_quotes} is a scientific graphics library written by David H. Munro of Lawrence Livermore National Laboratory (LLNL). It features support for three common graphics output devices: X Windows, (Color) PostScript, and ANSI/ISO Standard Computer Graphics Metafiles (CGM). The library is small (written directly to Xlib), portable, efficient, and full-featured. It produces X versus Y plots with {open_quotes}good{close_quotes} tick marks and tick labels, 2-dimensional quadrilateral mesh plots with contours, vector fields, or pseudo color maps on such meshes, with 3-dimensional plots on the way. The Python Gist module utilizes the new {open_quotes}Numeric{close_quotes} module due to J. Hugunin and others. It is therefore fast and able to handle large datasets. The Gist module includes an X Windows event dispatcher which can be dynamically added (e.g., via importing a dynamically loaded module) to the Python interpreter after a simple two-line modification to the Python core. This makes fast mouse-controlled zoom, pan, and other graphic operations available to the researcher while maintaining the usual Python command-line interface. Munro`s Gist library is already freely available. The Python Gist module is currently under review and is also expected to qualify for unlimited release.
Date: May 8, 1996
Creator: Busby, L.E.
Object Type: Article
System: The UNT Digital Library
Sediment isotope tomography (SIT) model version 1 (open access)

Sediment isotope tomography (SIT) model version 1

Geochronology using {sup 210}Pb is the principal method used to quantify sediment accumulation in rapidly depositing aquatic environments such as lakes, estuaries, continental shelves, and submarine canyons. This method is based on the radioactive decay of {sup 210}Pb with depth in a column of sediment. The decay through time of {sup 210}Pb P(t) is governed by the exponential law P(t) = P{sub 0} exp( -{lambda}t) where P{sub 0} is the surficial concentration at time t = 0, and {lambda} is the decay constant (3.114 {sm_bullet} 10{sup -2} year [yr]{sup -1} for {sup 210}Pb). If the sedimentation rate is constant, then elapsed time t is connected to burial depth x, through x = Vt where V is the sedimentation velocity. Accordingly, P(x) = P{sub 0}exp( -{lambda}x/V). The sedimentation velocity is obtained from an exponential fit to the measured {sup 210}Pb data P(x), with depth x.
Date: March 8, 1996
Creator: Carroll, J. & Abraham, J.D.
Object Type: Report
System: The UNT Digital Library
Approximate option pricing (open access)

Approximate option pricing

As increasingly large volumes of sophisticated options (called derivative securities) are traded in world financial markets, determining a fair price for these options has become an important and difficult computational problem. Many valuation codes use the binomial pricing model, in which the stock price is driven by a random walk. In this model, the value of an n-period option on a stock is the expected time-discounted value of the future cash flow on an n-period stock price path. Path-dependent options are particularly difficult to value since the future cash flow depends on the entire stock price path rather than on just the final stock price. Currently such options are approximately priced by Monte carlo methods with error bounds that hold only with high probability and which are reduced by increasing the number of simulation runs. In this paper the authors show that pricing an arbitrary path-dependent option is {number_sign}-P hard. They show that certain types f path-dependent options can be valued exactly in polynomial time. Asian options are path-dependent options that are particularly hard to price, and for these they design deterministic polynomial-time approximate algorithms. They show that the value of a perpetual American put option (which can be computed …
Date: April 8, 1996
Creator: Chalasani, P.; Saias, I. & Jha, S.
Object Type: Report
System: The UNT Digital Library
Bench-Scale Studies With Mercury Contaminated SRS Soil (open access)

Bench-Scale Studies With Mercury Contaminated SRS Soil

The Savannah River Technology Center (SRTC) has been charactered by the Department of Enregy (DOE) - Office of Technology Development (OTD) to investigate vitrification technology for the treatment of Low Level Mixed Wastes (LLMW). In fiscal year 1995, LLW streams containing mercury and organics were targeted. This report will present the results of studies with mercury contaminated waste. In order to successfully apply vitrification technology to LLMW, the types and quantities of glass forming additives necessary for producing homogeneous glasses from the wastes had to be determined, and the treatment for the mercury portion had to also be determined. The selected additives had to ensure that a durable and leach resistant waste form was produced, while the mercury treatment had to ensure that hazardous amounts of mercury were not released into the environment.
Date: May 8, 1996
Creator: Cicero, C.A.
Object Type: Report
System: The UNT Digital Library
Surface moisture measurement system electromagnetic induction probe calibration technique (open access)

Surface moisture measurement system electromagnetic induction probe calibration technique

The Surface Moisture Measurement System (SMMS) is designed to measure the moisture concentration near the surfaces of the wastes located in the Hanford Site tank farms. This document describes a calibration methodology to demonstrate that the Electromagnetic Induction (EMI) moisture probe meets relevant requirements in the `Design Requirements Document (DRD) for the Surface Moisture Measurement System.` The primary purpose of the experimental tests described in this methodology is to make possible interpretation of EMI in-tank surface probe data to estimate the surface moisture.
Date: July 8, 1996
Creator: Crowe, R. D.
Object Type: Report
System: The UNT Digital Library
Slurry phase iron catalysts for indirect coal liquefaction. First semi-annual progress report, July 5, 1995--January 4, 1996 (open access)

Slurry phase iron catalysts for indirect coal liquefaction. First semi-annual progress report, July 5, 1995--January 4, 1996

Objectives are to study factors controlling attrition resistance of slurry phase Fe catalysts, synthesize novel precipitated catalysts that overcome some of the limitations of current generation catalysts, and study catalyst-binder interactions using model catalysts. A study of Fe/silica (binder) interactions has been started. Study of effects of Cu on reducibility of Fe catalysts showed that small amounts of Cu can facilitate reduction of Fe{sub 2}O{sub 3} to {alpha}-Fe. Work with Nancy Jackson (Sandia) on carbon deposits in Fe F-T catalysts showed good correlation between peak temperature in TPR and the carbon as seen by TEM. Analyses of samples from Dr. Burtron Davis (U. KY) by XRD and TEM showed that the active catalyst contains small crystallites of iron carbide while the deactivated catalyst had significant transformation into large magnetite crystals. It is felt that improper passivation of these catalysts can lead to mis-identification of the phase in working F-T catalysts.
Date: February 8, 1996
Creator: Datye, A.K.
Object Type: Report
System: The UNT Digital Library
Soft x-ray generation in gases with an ultrashort pulse laser (open access)

Soft x-ray generation in gases with an ultrashort pulse laser

An experimental investigation of soft x-ray production resulting from the interaction of intense near infra-red laser radiation with gases is presented in this thesis. Specifically, soft x-ray generation through high order harmonic generation or exploiting intense inverse bremsstrahlung heating is examined. Most of these studies are conducted with femtosecond, terawatt class Cr:LiSrAlF{sub 6} (LiSAF) laser, though results derived from studies with other laser systems are presented as well. The majority of this work is devoted to experimental investigations, however, theoretical and computational models are developed to interpret the data. These studies are motivated by the possibility of utilizing the physics of intense laser/matter interactions as a potential compact source of bright x-rays. Consequently, the thrust of many of the experiments conducted is aimed at characterizing the x-rays produced for possible use in applications. In general, the studies of this manuscript fall into three categories. First, a unique 130 fs, 8 TW laser that is based on chirped pulse amplification, is described, and its performance is evaluated. The generation of x-rays through high order harmonics is then discussed with emphasis on characterizing and optimizing harmonic generation. Finally, the generation of strong, incoherent x-ray radiation by the intense irradiation of large (>1,000 …
Date: January 8, 1996
Creator: Ditmire, T.R.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Evaluation of concrete masonry unit walls for lateral natural phenomena hazards loads (open access)

Evaluation of concrete masonry unit walls for lateral natural phenomena hazards loads

Older single-story facilities (Pre-1985 vintage) are commonly constructed of structural steel framing with concrete masonry unit (CMU) walls connected to columns and roof girders of the steel framing system. The CMU walls are designed for lateral wind and seismic loads (perpendicular to the wall) and transmit shear loads from the roof diaphragm to the foundation footings. The lateral loads normally govern their design. The structural framing system and the roof diaphragm system are straight forward when analyzing or upgrading the structure for NPH loads. Because of a buildings design vintage, probable use of empirical methodology, and poor design basis documentation (and record retention); it is difficult to qualify or upgrade CMU walls for lateral Natural Phenomena Hazards (NPH) loads in accordance with References 1, 2 and 3. This paper discusses three analytical approaches and/or techniques (empirical, working stress and yield line) to determine the collapse capacity of a laterally loaded CMU wall, and compares their results
Date: March 8, 1996
Creator: Faires, W.E. Jr.
Object Type: Article
System: The UNT Digital Library
Tank characterization report for single-shell tank 241-B-104 (open access)

Tank characterization report for single-shell tank 241-B-104

This document summarizes information on the historical uses, present status, and the sampling and analysis results of waste stored in Tank 241-B-104. Sampling and analyses meet safety screening and historical data quality objectives. This report supports the requirements of Tri-party Agreement Milestone M-44-09. his characterization report summoned the available information on the historical uses and the current status of single-shell tank 241-B-104, and presents the analytical results of the June 1995 sampling and analysis effort. This report supports the requirements of the Hanford Federal Facility Agreement and Consent Order Milestone M-44-09 (Ecology et al. 1994). Tank 241-B-104 is a single-shell underground waste storage tank located in the 200 East Area B Tank Farm on the Hanford Site. It is the first tank in a three-tank cascade series. The tank went into service in August 1946 with a transfer of second-cycle decontamination waste generated from the bismuth phosphate process. The tank continued to receive this waste type until the third quarter of 1950, when it began receiving first-cycle decontamination waste also produced during the bismuth phosphate process. Following this, the tank received evaporator bottoms sludge from the 242-B Evaporator and waste generated from the flushing of transfer lines. A description and …
Date: April 8, 1996
Creator: Field, J. G.
Object Type: Report
System: The UNT Digital Library
Charge-density wave and magnetic phase diagram of chromium alloys (open access)

Charge-density wave and magnetic phase diagram of chromium alloys

The magnetic phase diagrams of all dilute Cr alloys can be explained by a simple theoretical model with coupled spin- and charge-density waves and a finite electron reservoir. If the charge-density wave and electron reservoir are sufficiently large, the paramagnetic to commensurate spin-density wave transition becomes strongly first order, as found in Cr{sub 1- x}Fe{sub x} and Cr{sub 1-x}Si{sub x} alloys. The observed discontinuity of the slope dT{sub N}/dx at the triple point and the bending of the CI phase boundary are also natural consequences of this model.
Date: August 8, 1996
Creator: Fishman, R.S. & Jiang, X.W.
Object Type: Article
System: The UNT Digital Library
Masonry infill performance during the Northridge earthquake (open access)

Masonry infill performance during the Northridge earthquake

The response of masonry infills during the 1994 Northridge, California earthquake is described in terms of three categories: (1) lowrise and midrise structures experiencing large near field seismic excitations, (2) lowrise and midrise structures experiencing moderate far field excitation, and (3) highrise structures experiencing moderate far field excitation. In general, the infills provided a positive beneficial effect on the performance of the buildings, even those experiencing large peak accelerations near the epicenter. Varying types of masonry infills, structural frames, design conditions, and construction deficiencies were observed and their performance during the earthquake indicated. A summary of observations of the performance of infills in other recent earthquakes is given. Comparison with the Northridge earthquake is made and expected response of infill structures in lower seismic regions of the central and eastern United States is discussed.
Date: March 8, 1996
Creator: Flanagan, R.D.; Bennett, R.M.; Fischer, W.L. & Adham, S.A.
Object Type: Report
System: The UNT Digital Library
Performance of keck adaptive optics with sodium laser guide star (open access)

Performance of keck adaptive optics with sodium laser guide star

The Keck telescope adaptive optics system is designed to optimize performance in he 1 to 3 micron region of observation wavelengths (J, H, and K astronomical bands). The system uses a 249 degree of freedom deformable mirror, so that the interactuator spacing is 56 cm as mapped onto the 10 meter aperture. 56 cm is roughly equal to r0 at 1.4 microns, which implies the wavefront fitting error is 0.52 ({lambda}/2{pi})({ital d}/{ital r}{sub 0}){sup 5/6} = 118 nm rms. This is sufficient to produce a system Strehl of 0.74 at 1.4 microns if all other sources of error are negligible, which would be the case with a bright natural guidestar and very high control bandwidth. Other errors associated with the adaptive optics will however contribute to Strehl degradation, namely, servo bandwidth error due to inability to reject all temporal frequencies of the aberrated wavefront, wavefront measurement error due to finite signal-to-noise ratio in the wavefront sensor, and, in the case of a laser guidestar, the so-called cone effect where rays from the guidestar beacon fail to sample some of the upper atmosphere turbulence. Cone effect is mitigated considerably by the use of the very high altitude sodium laser guidestar (90 …
Date: March 8, 1996
Creator: Gavel, D. T.; Olivier, S. & Brase, J.
Object Type: Article
System: The UNT Digital Library
Amperometric detection and electrochemical oxidation of aliphatic amines and ammonia on silver-lead oxide thin-film electrodes (open access)

Amperometric detection and electrochemical oxidation of aliphatic amines and ammonia on silver-lead oxide thin-film electrodes

This thesis comprises three parts: Electrocatalysis of anodic oxygen-transfer reactions: aliphatic amines at mixed Ag-Pb oxide thin-film electrodes; oxidation of ammonia at anodized Ag-Pb eutectic alloy electrodes; and temperature effects on oxidation of ethylamine, alanine, and aquated ammonia.
Date: January 8, 1996
Creator: Ge, Jisheng
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Thomson scattering in the corona of laser-produced gold plasmas (open access)

Thomson scattering in the corona of laser-produced gold plasmas

Thomson scattering measurements of the electron temperature in laser- produced gold plasmas are presented. We irradiated a flat gold disk target with one laser beam of the Nova laser facility. A second laser beam probed the plasma at a distance of 500{mu}m with temporally resolved Thomson scattering. The electron temperature measurements are compared with hydrodynamic simulations using the code LASNEX for experiments applying smoothed and unsmoothed heater beams. In case of an unsmoothed heater beam the simulations predict temperatures which are about 40% higher than our measured data. Although the agreement is improved for a smoothed heater beam, discrepancies exist in the decay phase of the plasma. We discuss possible explanations for these observations.
Date: May 8, 1996
Creator: Glenzer, S. H.; Back, C. A.; Estabrook, K. G. & MacGowan, B. J.
Object Type: Article
System: The UNT Digital Library
Molecular dynamics modeling of microstructure evolution during growth of amorphous carbon films (open access)

Molecular dynamics modeling of microstructure evolution during growth of amorphous carbon films

Amorphous carbon films approximately 20 nm thick are used throughout the computer industry as protective coatings on magnetic storage disks. As storage densities increase, the role of the overcoat becomes increasingly important because of smaller spacings between the recording head and the spinning disk. Furthermore, future-generation disks call for an overcoat thickness of 5 nm or less. These small length scales and the high speed of the spinning disk (10-30 m/s) suggest that a molecular dynamics (MD) model might provide useful insight into friction and wear mechanisms when the head and disk make contact. One of the necessary inputs required to carry out such an MD model is a specification of the position of all the atoms in the simulation, i.e. a detailed model of the material microstructure. Such a detailed understanding of the microstructure of amorphous carbon overcoats does not presently exist. Neutron and electron diffraction studies demonstrate that the material is amorphous. Previous classical MD simulations yield pair distribution functions in qualitative agreement with the diffraction studies, but they all differ in detail. More recent, quantum-mechanical tight-binding MD (TBMD) studies give a better description of the interatomic interactions and the chemical hybridization (sp{sup 2}-graphite-like versus sp{sup 3}-diamond-like). However, …
Date: January 8, 1996
Creator: Glosli, J.N.; Belak, J. & Philpott, M.R.
Object Type: Article
System: The UNT Digital Library
Fissile material disposition program: Screening of alternate immobilization candidates for disposition of surplus fissile materials (open access)

Fissile material disposition program: Screening of alternate immobilization candidates for disposition of surplus fissile materials

With the end of the Cold War, the world faces for the first time the need to dismantle vast numbers of ``excess`` nuclear weapons and dispose of the fissile materials they contain, together with fissile residues in the weapons production complex left over from the production of these weapons. If recently agreed US and Russian reductions are fully implemented, tens of thousands of nuclear weapons, containing a hundred tons or more of plutonium and hundreds of tonnes* of highly enriched uranium (HEU), will no longer be needed worldwide for military purposes. These two materials are the essential ingredients of nuclear weapons, and limits on access to them are the primary technical barrier to prospective proliferants who might desire to acquire a nuclear weapons capability. Theoretically, several kilograms of plutonium, or several times that amount of HEU, is sufficient to make a nuclear explosive device. Therefore, these materials will continue to be a potential threat to humanity for as long as they exist.
Date: January 8, 1996
Creator: Gray, L.W.
Object Type: Report
System: The UNT Digital Library