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Advanced Techniques for Fourier Transform Wavefront Reconstruction (open access)

Advanced Techniques for Fourier Transform Wavefront Reconstruction

The performance of Fourier transform (FT) reconstructors in large adaptive optics systems with Shack-Hartmann sensors and a deformable mirror is analyzed. FT methods, which are derived for point-based geometries, are adapted for use on the continuous systems. Analysis and simulation show how to compensate for effects such as misalignment of the deformable mirror and wavefront sensor gain. Further filtering methods to reduce noise and improve performance are presented. All these modifications can be implemented at the filtering stage, preserving the speed of FT reconstruction. Simulation of a large system shows how compensated FT methods can have equivalent or better performance to slower vector-matrix-multiply reconstructions.
Date: August 5, 2002
Creator: Poyneer, L A
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 104, No. 121, Ed. 1 Monday, August 5, 2002 (open access)

Altus Times (Altus, Okla.), Vol. 104, No. 121, Ed. 1 Monday, August 5, 2002

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: August 5, 2002
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Sun (Alvin, Tex.), Vol. 111, No. 62, Ed. 1 Monday, August 5, 2002 (open access)

The Alvin Sun (Alvin, Tex.), Vol. 111, No. 62, Ed. 1 Monday, August 5, 2002

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: August 5, 2002
Creator: Schwind, Jim & Holton, Kathleen
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 80, No. 252, Ed. 1 Monday, August 5, 2002 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 80, No. 252, Ed. 1 Monday, August 5, 2002

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: August 5, 2002
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Beatrice Alba Martinez representará a Dallas en el Consejo Directivo de DART (open access)

Beatrice Alba Martinez representará a Dallas en el Consejo Directivo de DART

News release about the appointment of Beatrice Martinez to the DART Board of Directors, representing the city of Dallas.
Date: August 5, 2002
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
Beatrice Alba Martinez to represent Dallas on DART Board of Directors (open access)

Beatrice Alba Martinez to represent Dallas on DART Board of Directors

News release about the appointment of Beatrice Martinez to the DART Board of Directors, representing the city of Dallas.
Date: August 5, 2002
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
Bosnia: U.S. Military Operations (open access)

Bosnia: U.S. Military Operations

This report outlines U.S. military operations in Bosnia and discusses issues such as U.S. and Allied Participation in Bosnia Peacekeeping (IFOR/SFOR), duration, cost, arms control and military assistance. This report also includes most recent development, background analysis, and legislation.
Date: August 5, 2002
Creator: Bowman, Steven R.
Object Type: Report
System: The UNT Digital Library
Cambios Propuestos de Servicio de Autobús presentados en juntas comunitarias (open access)

Cambios Propuestos de Servicio de Autobús presentados en juntas comunitarias

News release concerning DART public meetings to gather input on proposed bus service changes in coordination with the agency's light rail expansion.
Date: August 5, 2002
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
Chamber wall response to target implosion in inertial fusion reactors : new and critical assessments. (open access)

Chamber wall response to target implosion in inertial fusion reactors : new and critical assessments.

The chamber walls in inertial fusion energy (IFE) reactors are exposed to harsh conditions following each target implosion. Key issues of the cyclic IFE operation include intense photon and ion deposition, wall thermal and hydrodynamic evolution, wall erosion and fatigue lifetime, and chamber clearing and evacuation to ensure desirable conditions prior to target implosion. Several methods for wall protection have been proposed in the past, each having its own advantages and disadvantages. These methods include use of solid bare walls, gas-filled cavities, and liquid walls/jets. Detailed models have been developed for reflected laser light, emitted photons, and target debris deposition and interaction with chamber components and have been implemented in the comprehensive HEIGHTS software package. The hydrodynamic response of gas filled cavities and photon radiation transport of the deposited energy has been calculated by means of new and advanced numerical techniques. Fragmentation models of liquid jets as a result of the deposited energy have also been developed, and the impact on chamber clearing dynamics has been evaluated. The focus of this study is to critically assess the reliability and the dynamic response of chamber walls in various proposed protection methods for IFE systems. Of particular concern is the effect on …
Date: August 5, 2002
Creator: Hassanein, A. & Morozov, V.
Object Type: Article
System: The UNT Digital Library
Chemical Weapons Convention: Issues for Congress (open access)

Chemical Weapons Convention: Issues for Congress

The CWC bans the development, production, stockpiling, and use of chemical weapons by members signatories. It also requires the destruction of all chemical weapons stockpiles and production facilities. Neither the United States nor Russia will be able to meet the original CWC’s deadlines for destruction of their CW stockpiles, and have been granted extensions to at least 2012. The Convention provides the most extensive and intrusive verification regime of any arms control treaty, extending its coverage to not only governmental but also civilian facilities. The Convention also requires export controls and reporting requirements on chemicals that can be used as warfare agents and their precursors. The CWC establishes the Organization for the Prohibition of Chemical Weapons (OPCW) to oversee the Convention’s implementation.
Date: August 5, 2002
Creator: Bowman, Steven R.
Object Type: Report
System: The UNT Digital Library
CHEMICALLY BONDED CEMENTS FROM BOILER ASH AND SLUDGE WASTES. PHASE I REPORT AUGUST 1997 - JULY 1998 (open access)

CHEMICALLY BONDED CEMENTS FROM BOILER ASH AND SLUDGE WASTES. PHASE I REPORT AUGUST 1997 - JULY 1998

In exploring methods to recycle boiler ash (BA) and waste water treatment sludge (WWTS), by-products generated from Keyspan's power plants, into commercially viable materials, we synthesized chemically bonded cements (CBC) offering the following three specific characteristics; (1) immobilization of hazardous heavy metals, such as Pb, Ni, and V, (2) rapid hardening and setting properties, and (3) development of high mechanical strength. The CBCs were prepared through an acid-base reaction between these by-products acting as the solid base reactants and the sodium polyphosphate solution as the cement-forming acid reactant, followed by a hydrating reaction. Furthermore, two additives, the calcium aluminate cements (CAC) and the calcium silicate cements (CSC) were incorporated into the CBC systems to improve their properties. Using a CBC formulation consisting of 53.8 wt% WWTS, 23.1 wt% CSC, and 23.1 wt% [40 wt% -(-NaPO{sub 3}-)-{sub n}]{sub 2} the Toxicity Characteristics Leaching Procedure (TCLP) tests showed that the concentrations of Pb, Ni, and V metals leached out from the specimens were minimal. This formulation originally contained {approx} 28800 mg/kg of Pb, {approx} 6300 mg/kg of Ni, and {approx} 11130 mg/kg of V; the amounts leaching into the acid extraction fluid were only 0.15 mg/L of Pb, 0.15 mg/L of Ni, …
Date: August 5, 2002
Creator: SUGAMA,T. & YAGER,K.A.
Object Type: Report
System: The UNT Digital Library
Daily Journal (Perry, Okla.), Vol. 109, No. 153, Ed. 1 Monday, August 5, 2002 (open access)

Daily Journal (Perry, Okla.), Vol. 109, No. 153, Ed. 1 Monday, August 5, 2002

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: August 5, 2002
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
DART's Cowboys Flyer Hace ‘viajes por camino' fácil para fanáticos (open access)

DART's Cowboys Flyer Hace ‘viajes por camino' fácil para fanáticos

News release about DART's "Cowboy Flyer" shuttle service to Dallas Cowboy games.
Date: August 5, 2002
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
DART's Cowboys Flyer Makes 'road trips' easier for fans (open access)

DART's Cowboys Flyer Makes 'road trips' easier for fans

News release about DART's "Cowboy Flyer" shuttle service to Dallas Cowboy games.
Date: August 5, 2002
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
Evaluation of Possible Nuclear Magnetic Resonance Diagnostic Techniques for Tokamak Experiments (open access)

Evaluation of Possible Nuclear Magnetic Resonance Diagnostic Techniques for Tokamak Experiments

Potential applications of nuclear magnetic resonance (NMR) diagnostic techniques to tokamak experiments are evaluated. NMR frequencies for hydrogen isotopes and low-Z nuclei in such experiments are in the frequency range approximately equal to 20-200 MHz, so existing RF [radio-frequency] antennas could be used to rotate the spin polarization and to make the NMR measurements. Our tentative conclusion is that such measurements are possible if highly spin polarized H or (superscript)3He gas sources (which exist) are used to fuel these plasmas. In addition, NMR measurements of the surface layers of the first wall (without plasma) may also be possible, e.g., to evaluate the inventory of tritium inside the vessel.
Date: August 5, 2002
Creator: Zweben, S. J.; Kornack, T. W.; Majeski, D.; Schilling, G.; Skinner, C. H. & Wilson, R.
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, August 5, 2002 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, August 5, 2002

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: August 5, 2002
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
[Funeral Program for Joseph Hill, August 5, 2002] (open access)

[Funeral Program for Joseph Hill, August 5, 2002]

Funeral program for Mr. Joseph Hill, born March 16, 1920. The funeral was held August 5, 2002 at New Light Baptist Church, officiated by Rev. J. S. Smith. The funeral arrangements were made through Carter-Taylor-Williams Mortuary and he was buried in Meadowlawn Memorial Park in San Antonio, Texas.
Date: August 5, 2002
Creator: unknown
Object Type: Pamphlet
System: The Portal to Texas History
Infiltration Heat Recovery in Building Walls: Computational Fluid Dynamics Investigations Results (open access)

Infiltration Heat Recovery in Building Walls: Computational Fluid Dynamics Investigations Results

Conventional calculations of heating (and cooling) loads for buildings assume that conduction heat loss (or gain) through walls is independent of air infiltration heat loss (or gain). During passage through the building envelope, infiltrating air substantially exchanges heat wall insulation leading to partial recovery of heat conducted through the wall. The Infiltration Heat Recovery (IHR) factor was introduced to quantify the heat recovery and correct the conventional calculations. In this study, Computational Fluid Dynamics was used to calculate infiltration heat recovery under a range of idealized conditions, specifically to understand factors that influence it, and assess its significance in building heat load calculations. This study shows for the first time the important effect of the external boundary layers on conduction and infiltration heat loads. Results show (under the idealized conditions studied here) that (1) the interior details of the wall encountered in the leakage pa th (i.e., insulated or empty walls) do not greatly influence the IHR, the overall relative location of the cracks (i.e., inlet and outlet locations on the wall) has the largest influence on the IHR magnitude, (2) external boundary layers on the walls substantially contribute to IHR and (3) the relative error in heat load calculations …
Date: August 5, 2002
Creator: Abadie, Marc O.; Finlayson, Elizabeth U. & Gadgil, Ashok J.
Object Type: Report
System: The UNT Digital Library
Joyce Foreman representará a Dallas en el Consejo Directivo de DART (open access)

Joyce Foreman representará a Dallas en el Consejo Directivo de DART

News release about the appointment of Joyce Foreman to the DART Board of Directors, representing the city of Dallas.
Date: August 5, 2002
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
Joyce Foreman to represent Dallas on DART Board of Directors (open access)

Joyce Foreman to represent Dallas on DART Board of Directors

News release about the appointment of Joyce Foreman to the DART Board of Directors, representing the city of Dallas.
Date: August 5, 2002
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
Kosovo and Macedonia: U.S. and Allied Military Operations (open access)

Kosovo and Macedonia: U.S. and Allied Military Operations

None
Date: August 5, 2002
Creator: Bowman, Steven R.
Object Type: Report
System: The UNT Digital Library
A Metadata Approach to Preservation of Digital Resources: The University of North Texas Libraries' Experience (open access)

A Metadata Approach to Preservation of Digital Resources: The University of North Texas Libraries' Experience

Article discussing metadata approaches to preservation of digital resources and the experiences of the University of North Texas (UNT) Libraries.
Date: August 5, 2002
Creator: Alemneh, Daniel Gelaw; Hastings, Samantha Kelly & Hartman, Cathy Nelson
Object Type: Article
System: The UNT Digital Library
Modeling the Evolution of Strength During Wire Drawing (open access)

Modeling the Evolution of Strength During Wire Drawing

Extensive plastic deformation during wire drawing is commonly used to produce steel wires with very high strengths. Typically these steels are eutectoid and hypereutectoid steels and drawing strains up to 4 are used during processing. The resulting materials can have tensile strengths in excess of 4000 MPa. The evolution of microstructure and the strengthening mechanisms resulting from wire drawing have been studied for eutectoid and hypereutectoid steels. Strength has been shown to be a function of pearlite colony size, interlamellar spacing and the size of the stable dislocation cells that are produced during wire drawing. The results have been used to model the evolution of strength during wire drawing. Model predictions for the evolution of tensile strength with drawing strain show excellent agreement with data derived from a number of eutectoid and hyperectectoid steels as a function of drawing strain.
Date: August 5, 2002
Creator: Lesuer, D R; Syn, C K & Sherby, O D
Object Type: Article
System: The UNT Digital Library
Monitoring Carbon Dioxide Sequestration Using Electrical Resistance Tomography (ERT): A Minimally Invasive Method (open access)

Monitoring Carbon Dioxide Sequestration Using Electrical Resistance Tomography (ERT): A Minimally Invasive Method

Successful geologic sequestration of carbon dioxide (CO{sub 2}), will require monitoring the CO{sub 2} injection to confirm the performance of the caprock/reservoir system, assess leaks and flow paths, and understand the geophysical and geochemical interactions between the CO{sub 2} and the geologic minerals and fluids. Electrical methods are especially well suited for monitoring processes involving fluids, as electrical properties are sensitive to the presence and nature of the formation fluids. High resolution tomographs of electrical properties are now used for site characterization and to monitor subsurface migration of fluids (i.e., leaking underground tanks, infiltration events, steam floods, contaminant movement, and to assess the integrity of engineered barriers). When electrical resistance tomography (ERT) imaging can be performed using existing well casings as long electrodes, the method is nearly transparent to reservoir operators, and reduces the need for additional drilling. Using numerical simulations and laboratory experiments, we have conducted sensitivity studies to determine the potential of ERT methods to detect and monitor the migration of CO{sub 2} in the subsurface. These studies have in turn been applied to the design and implementation of the first field casing surveys conducted in an oil field undergoing a CO{sub 2} flood.
Date: August 5, 2002
Creator: Newmark, R. L.; Ramirez, A. L. & Daily, W. D.
Object Type: Article
System: The UNT Digital Library