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Horizontal and Slant-Path Surveillance with Speckle Imaging (open access)

Horizontal and Slant-Path Surveillance with Speckle Imaging

A fundamental problem in providing high-quality surveillance images recorded over long horizontal or slant paths is the blurring caused by atmospheric turbulence, which reduces both the resolution and contrast. The objective of the work reported here is to develop a capability for long-range imaging through the atmosphere that is not limited by the atmosphere but only by the fundamental diffraction limit of the optics. This paper describes our recent horizontal and slant-path imaging experiments of point targets and extended scenes as well as simulations of point targets in comparison to experiment. We show the near-diffraction limited resolution results obtained using bispectral speckle-imaging techniques. The experiments were performed with an 8-inch diameter telescope placed either in a field, on a rooftop, or on a hillside and cover ranges of interest from 100 meters up to 10 km. The scenery includes resolution targets, people, vehicles, and other structures.
Date: August 19, 2002
Creator: Carrano, C J & Brase, J M
Object Type: Article
System: The UNT Digital Library
[Deposit summary and a handwritten note to Al Daniels] (open access)

[Deposit summary and a handwritten note to Al Daniels]

Deposit summary of $375.00 made on August 19, 2002, and a handwritten note to Al Daniels from Michael Milliken discussing deposit.
Date: August 19, 2002
Creator: unknown
Object Type: Letter
System: The UNT Digital Library
Reconciliation Report (open access)

Reconciliation Report

Reconciliation report with an ending account balance of $1,622.07 reconciled for the period ending on August 19, 2002.
Date: August 19, 2002
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Mutual passivation of electrically active and isovalent impurities (open access)

Mutual passivation of electrically active and isovalent impurities

None
Date: August 19, 2002
Creator: Yu, K.M.; Walukiewicz, W.; Wu, J.; Mars, D.E.; Chamberlin, D.R.; Scarpulla, M.A. et al.
Object Type: Article
System: The UNT Digital Library
Scattering in a magnetic field (open access)

Scattering in a magnetic field

The fixed target program at Fermilab has come to an end. New projects are in the planning stage. Among them is a muon storage ring. Up to the present, all storage rings in high-energy physics have carried stable particles, namely the electron and proton and their antiparticles. The muon is unstable and decays with a mean lifetime of 2.0 x 10{sup -6} sec. Two types of cooling have been used in the past. One is stochastic cooling where an electrode is used to detect the positions of the particles and send a signal to another position across the ring. Through successive applications of this technique, the phase space is ultimately greatly reduced and beams can be made to collide with a useful event rate. The second type of cooling is electron cooling. Here protons and electrons are made to travel together for a short distance. Equipartition causes transfer of transverse energy of the protons to that of the electrons. Neither of these methods is fast enough to allow acceleration of a sufficient number of muons up to maximum energy before they decay. A new method known as ionization cooling has been proposed.[1] The muons are cooled by passing them through …
Date: August 19, 2002
Creator: Carey, David C.
Object Type: Article
System: The UNT Digital Library
Moderator Detritiation at the Savannah River Plant (open access)

Moderator Detritiation at the Savannah River Plant

To explore ways to reduce unnecessary reactor tritium concentration dosages in Savannah River Plant heavy water moderator by 90 percent, a study was made of processes and their implementation.
Date: August 19, 2002
Creator: Baumgarten, P.K.
Object Type: Article
System: The UNT Digital Library
Localized Measurement of Turbulent Fluctuations in Tokamaks with Coherent Scattering of Electromagnetic Waves (open access)

Localized Measurement of Turbulent Fluctuations in Tokamaks with Coherent Scattering of Electromagnetic Waves

Localized measurements of short-scale turbulent fluctuations in tokamaks are still an outstanding problem. In this paper, the method of coherent scattering of electromagnetic waves for the detection of density fluctuations is revisited. Results indicate that the proper choice of frequency, size and launching of the probing wave can transform this method into an excellent technique for high-resolution measurements of those fluctuations that plasma theory indicates as the potential cause of anomalous transport in tokamaks. The best spatial resolution can be achieved when the range of scattering angles corresponding to the spectrum of fluctuations under investigation is small. This favors the use of high frequency probing waves, such as those of far infrared lasers. The application to existing large tokamaks is discussed.
Date: August 19, 2002
Creator: Mazzucato, E.
Object Type: Report
System: The UNT Digital Library
Electrophoretic and structural studies of DNA-directed Au nanoparticle groupings (open access)

Electrophoretic and structural studies of DNA-directed Au nanoparticle groupings

None
Date: August 19, 2002
Creator: Zanchet, Daniela; Micheel, Christine M.; Parak, Wolfgang J.; Gerion, Daniele; Williams, Shara C. & Alivisatos, A. Paul
Object Type: Article
System: The UNT Digital Library
Procedure for Setting Up the Transfer Lines for the Sns. (open access)

Procedure for Setting Up the Transfer Lines for the Sns.

This paper describes the procedures for setting up the transfer lines for the Spallation Neutron Source (SNS). The High Energy Beam Transfer (HEBT) is about 170 meters long and has two achromat sections, an energy corrector cavity, energy spreader cavity, and transverse and longitudinal collimators. The Ring to Target Beam Transfer (RTBT) line is about 150 meters long has an achromat, transverse collimators and a beam spreader section. It will be shown that with the available diagnostics one can first characterize the incoming beam in both lines and then, with types and locations of the diagnostics and beam tuning ''knobs'', set up to deliver an output beam with the desired properties.
Date: August 19, 2002
Creator: Raparia, D.; Lee, Y. Y.; Weng, W. T. & Wei, J.
Object Type: Article
System: The UNT Digital Library
ANL/CRIEPI collaborative program for evaluation of irradiated EBR-II stainless steels. (open access)

ANL/CRIEPI collaborative program for evaluation of irradiated EBR-II stainless steels.

The objective of this collaboration between Argonne National Laboratory (ANL) and the Central Research Institute of Electric Power Industry (CRIEPI) is to evaluate the effects of long-term, low-dose neutron exposure on the mechanical properties, dimensional stability, and associated microstructural changes of reactor structural materials. ANL believes that material data obtained from components irradiated in EBR-II provide valuable information that is useful for LWR plant life extension. CRIEPI is currently conducting research on many aspects of materials aging of LWR components including irradiation damage. Therefore, ANL and CRIEPI have decided to perform the following joint work, which is of interest to both laboratories and continues the collaborative relationship between the two labs. The program was initiated in February of 1999. Samples were taken from two separate subassemblies, designated S1951 and S1952. These subassemblies were constructed of 20% cold-worked Type 316 stainless steel. The samples from these subassemblies were irradiated at temperatures from 371-390 C to doses up to 56 dpa. The examinations in this program included: immersion density, microhardness, microstructure, and tensile properties. The material history, test plan, results of measurements, and discussion of results are included in this report.
Date: August 19, 2002
Creator: Allen, T.; Cole, J.; Tsai, H.; Jensen, R.; Bunde, K.; Ohta, J. et al.
Object Type: Report
System: The UNT Digital Library
Dostoman Code: A Compartmental Pathways Computer Model of Contaminant Transport (open access)

Dostoman Code: A Compartmental Pathways Computer Model of Contaminant Transport

Assessing the impact of radioactive and hazardous chemical waste disposal on man is an important problem in environmental science and engineering. This report illustrates the mathematical evolution of the compartmental model from small to large systems and provides examples of the use of the compartmental approach in analysis of transport of radionuclide and chemical contaminants.
Date: August 19, 2002
Creator: King, C.M.
Object Type: Report
System: The UNT Digital Library
Linac Energy Manipulation for Longitudinal Phase Space Painting for Sns Ring. (open access)

Linac Energy Manipulation for Longitudinal Phase Space Painting for Sns Ring.

Control of instabilities and halo losses are important issues for a high beam power storage ring like the Spallation Neutron Source (SNS). One of the important issues is proper transverse and longitudinal phase space painting. The former is well studied and in this paper we discuss a robust way to achieve longitudinal phase space painting into a ring. Energy jitter correction and programmable energy spread are essential for controlling losses during the 1000 turn injection into the accumulator ring. Energy correction is needed to combat linac cavity amplitude and phase errors. Adequate energy spread is required to provide Landau damping in the accumulator ring during the accumulation process. Two CCL cavities, one for energy correction and the other for creating energy spread, are used for this purpose.
Date: August 19, 2002
Creator: Lee, Y. Y.; Blaskiewicz, M.; Fedotov, A.; Raparia, D.; Beebe-Wang, J.; Weng, W. T. et al.
Object Type: Article
System: The UNT Digital Library
Weatherford Inclined Wellbore Construction (open access)

Weatherford Inclined Wellbore Construction

The Rocky Mountain Oilfield Testing Center (RMOTC) has recently completed construction of an inclined wellbore with seven (7) inch, twenty-three (23) pound casing at a total depth of 1296 feet. The inclined wellbore is near vertical to 180 feet with a build angle of approximately 4.5 degrees per hundred feet thereafter. The inclined wellbore was utilized for further proprietary testing after construction and validation. The wellbore is available to other companies requiring a cased hole environment with known deviation out to fifty degrees (50) from vertical. The wellbore may also be used by RMOTC for further deepening into the fractured shales of the Steele and Niobrara formation.
Date: August 19, 2002
Creator: Schulte, R.
Object Type: Report
System: The UNT Digital Library
A comparison of optimization software for mesh shape-quality improvement problems. (open access)

A comparison of optimization software for mesh shape-quality improvement problems.

Simplicial mesh shape-quality can be improved by optimizing an objective function based on tetrahedral shape measures. If the objective function is formulated in terms of all elements in a given mesh rather than a local patch, one is confronted with a large-scale, nonlinear, constrained numerical optimization problem. We investigate the use of six general-purpose state-of-the-art solvers and two custom-developed methods to solve the resulting large-scale problem. The performance of each method is evaluated in terms of robustness, time to solution, convergence properties, and scalability on several two- and three-dimensional test cases.
Date: August 19, 2002
Creator: Freitag, L.; Knupp, P.; Munson, T. & Shontz, S.
Object Type: Article
System: The UNT Digital Library
Reactor Room Experimental SF6 Tests to Determine Probable Stack Activity Response to Radioactive Releases (open access)

Reactor Room Experimental SF6 Tests to Determine Probable Stack Activity Response to Radioactive Releases

This study was performed to obtain information that could be useful for obtaining an early estimate of the probable total stack activity monitor response in the event of an accidental release of radioactive activity in the process room.
Date: August 19, 2002
Creator: Cooper, R. E.
Object Type: Report
System: The UNT Digital Library
Laser Beam Profile Monitor Development at Bnl for Sns. (open access)

Laser Beam Profile Monitor Development at Bnl for Sns.

A beam profile monitor for H{sup -} beams using laser photoneutralization is being developed at Brookhaven National Laboratory [1] for use on the Spallation Neutron Source (SNS) [2]. An H{sup -} ion has a first ionization potential of 0.75eV and can be neutralized by light from a Nd:YAG laser ({lambda}=1064nm). To measure beam profiles, a narrow laser beam is passed through the ion beam neutralizing a portion of the H{sup -} beam struck by the laser, and the perturbation of the beam current caused by the laser is measured. The laser trajectory is stepped across the ion beam generating a transverse profile. Proof-of-principle experiments were done at 750keV and 200MeV. Also a compact scanner prototype was used at Lawrence Berkeley National Laboratory (LBNL) [3] during commissioning of the SNS RFQ.
Date: August 19, 2002
Creator: Connolly, R.; Cameron, P.; Cupolo, J.; Dawson, C.; Degen, C.; Della Penna, A. et al.
Object Type: Article
System: The UNT Digital Library
Trade-offs between fuel economy and NOx emissions using fuzzy logic control. (open access)

Trade-offs between fuel economy and NOx emissions using fuzzy logic control.

The Center for Transportation Research at the Argonne National Laboratory (ANL) supports the DOE by evaluating advanced automotive technologies in a systems context. ANL has developed a unique set of compatible simulation tools and test equipment to perform an integrated systems analysis project from modeling through hardware testing and validation. This project utilized these capabilities to demonstrate the trade-off in fuel economy and Oxides of Nitrogen (NOx) emissions in a so-called ''pre-transmission'' parallel hybrid powertrain. The powertrain configuration (in simulation and on the dynamometer) consists of a Compression Ignition Direct Ignition (CIDI) engine, a Continuously Variable Transmission (CVT) and an electric drive motor coupled to the CVT input shaft. The trade-off is studied in a simulated environment using PSAT{copyright} with different controllers (fuzzy logic and rule based) and engine models (neural network and steady state models developed from ANL data).
Date: August 19, 2002
Creator: Rousseau, Aymeric; Saglini, Sylvain; Jakov, Michael; Gray, Donald & Hardy, Keith
Object Type: Article
System: The UNT Digital Library
UV-Raman spectroscopy, X-ray photoelectron spectroscopy, and temperature programmed desorption studies of model and bulk heterogeneous catalysts (open access)

UV-Raman spectroscopy, X-ray photoelectron spectroscopy, and temperature programmed desorption studies of model and bulk heterogeneous catalysts

X-ray photoelectron spectroscopy (XPS) and Temperature Programmed Desorption (TPD) have been used to investigate the surface structure of model heterogeneous catalysts in ultra-high vacuum (UHV). UV-Raman spectroscopy has been used to probe the structure of bulk model catalysts in ambient and reaction conditions. The structural information obtained through UV-Raman spectroscopy has been correlated with both the UHV surface analysis and reaction results. The present day propylene and ethylene polymerization catalysts (Ziegler-Natta catalysts) are prepared by deposition of TiCl{sub 4} and a Al(Et){sub 3} co-catalyst on a microporous Mg-ethoxide support that is prepared from MgCl{sub 2} and ethanol. A model thin film catalyst is prepared by depositing metallic Mg on a Au foil in a UHV chamber in a background of TiCl{sub 4} in the gas phase. XPS results indicate that the Mg is completely oxidized to MgCl{sub 2} by TiCl{sub 4} resulting in a thin film of MgCl{sub 2}/TiCl{sub x}, where x = 2, 3, and 4. To prepare an active catalyst, the thin film of MgCl{sub 2}/TiCl{sub x} on Au foil is enclosed in a high pressure cell contained within the UHV chamber and exposed to {approx}1 Torr of Al(Et){sub 3}.
Date: August 19, 2002
Creator: Tewell, Craig R.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 80, No. 266, Ed. 1 Monday, August 19, 2002 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 80, No. 266, Ed. 1 Monday, August 19, 2002

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: August 19, 2002
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Relevance of Nuclear Weapons Clean-Up Experience to Dirty Bomb Response (open access)

Relevance of Nuclear Weapons Clean-Up Experience to Dirty Bomb Response

During the past 50 years, the United States has experienced 32 major nuclear weapons accidents, nine of which released special nuclear material to the environment. Response to these accidents, coupled with recovery experience following the Russian satellite reentry and weapons test site cleanup, form the basis for determining actions that might be required following a nuclear terrorist event involving the release of radioactive material. Though valuable information has been gained following the recovery from various commercial accidents, most notably the Chernobyl nuclear power plant failure and the dismantled radiography source in the Brazilian city of Goi nia, this paper will focus on the lessons learned from the U.S. nuclear weapons program.
Date: August 19, 2002
Creator: Vantine, H C & Crites, T R
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 104, No. 133, Ed. 1 Monday, August 19, 2002 (open access)

Altus Times (Altus, Okla.), Vol. 104, No. 133, Ed. 1 Monday, August 19, 2002

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: August 19, 2002
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Sun (Alvin, Tex.), Vol. 111, No. 64, Ed. 1 Monday, August 19, 2002 (open access)

The Alvin Sun (Alvin, Tex.), Vol. 111, No. 64, Ed. 1 Monday, August 19, 2002

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: August 19, 2002
Creator: Schwind, Jim & Holton, Kathleen
Object Type: Newspaper
System: The Portal to Texas History
Studies in Long-Term Noise Statistics Regional Climate Sensitivity and Predictability. Final Report (2003) (open access)

Studies in Long-Term Noise Statistics Regional Climate Sensitivity and Predictability. Final Report (2003)

Investing whether climate change signals can be easily detected from physical processes rather than raw data.
Date: August 19, 2002
Creator: Kim, K.
Object Type: Report
System: The UNT Digital Library
An overview of high voltage dielectric material for traveling wave kicker magnet application (open access)

An overview of high voltage dielectric material for traveling wave kicker magnet application

Pulsed high power fast kickers are being used to change beam trajectories in particle accelerators. The fast rise and fall time of pulse waveform demands a transmission line structure for the kicker deflector design. The ideal design will be parallel metal plates. However, it uses very long straight sections to achieve the required deflection. In accelerators with constrained straight sections, high permeability materials such as ferrite have to be used to gain deflection efficiency. The transmission line kicker magnet is also referred as traveling wave kicker magnet. Its construction is based on distributed L-C cells along the longitudinal direction. The magnetic cells and capacitive cells are interleaved to simulate the characteristic impedance of a transmission line to minimize pulse reflection, and provide adequate frequency bandwidth to transmit the kicker pulse with fast rise and fall time. The magnetic cells are usually made of ferrite ceramics, but the capacitive cells have been made with different materials. For traveling wave kickers with higher impedance, the parallel plate vacuum capacitor has been used in CERN and KEK design. Others have used ceramic capacitors, printed circuit boards, and high permittivity ceramics as the capacitive cell. The high dielectric material has the advantage of compactness …
Date: August 19, 2002
Creator: al., Wu Zhang et
Object Type: Article
System: The UNT Digital Library