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Altus Times (Altus, Okla.), Vol. 100, No. 28, Ed. 1 Tuesday, April 20, 1999 (open access)

Altus Times (Altus, Okla.), Vol. 100, No. 28, Ed. 1 Tuesday, April 20, 1999

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: April 20, 1999
Creator: Cole, Carol
Object Type: Newspaper
System: The Gateway to Oklahoma History
The APS SASE FEL : modeling and code comparison. (open access)

The APS SASE FEL : modeling and code comparison.

A self-amplified spontaneous emission (SASE) free-electron laser (FEL) is under construction at the Advanced Photon Source (APS). Five FEL simulation codes were used in the design phase: GENESIS, GINGER, MEDUSA, RON, and TDA3D. Initial comparisons between each of these independent formulations show good agreement for the parameters of the APS SASE FEL.
Date: April 20, 1999
Creator: Biedron, S. G.
Object Type: Article
System: The UNT Digital Library
The APS SASE FEL : status and commissioning results. (open access)

The APS SASE FEL : status and commissioning results.

A self-amplified spontaneous emission (SASE) free-electron laser (FEL) is under construction at the Advanced Photon Source (APS). Three gun systems, an rf-test area, laser room, numerous diagnostics, a transfer line at the end of the linac, and a new building, which will serve as the experimental hall, have been added. The only remaining items to be installed are the undulators into the beamline. Here, the additions to the APS in support of this project as well as commissioning results and future plans will be discussed.
Date: April 20, 1999
Creator: Milton, S. V.
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 77, No. 147, Ed. 1 Tuesday, April 20, 1999 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 77, No. 147, Ed. 1 Tuesday, April 20, 1999

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: April 20, 1999
Creator: Dobbs, Gary
Object Type: Newspaper
System: The Portal to Texas History
The Boerne Star (Boerne, Tex.), Vol. 94, No. 32, Ed. 1 Tuesday, April 20, 1999 (open access)

The Boerne Star (Boerne, Tex.), Vol. 94, No. 32, Ed. 1 Tuesday, April 20, 1999

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date: April 20, 1999
Creator: Keasling, Edna & Fierro, Jennifer
Object Type: Newspaper
System: The Portal to Texas History
Calculations of the self-amplified spontaneous emission performance of a free-electron laser. (open access)

Calculations of the self-amplified spontaneous emission performance of a free-electron laser.

The linear integral equation based computer code (RON: Roger Oleg Nikolai), which was recently developed at Argonne National Laboratory, was used to calculate the self-amplified spontaneous emission (SASE) performance of the free-electron laser (FEL) being built at Argonne. Signal growth calculations under different conditions are used for estimating tolerances of actual design parameters. The radiation characteristics are discussed, and calculations using an ideal undulator magnetic field and a real measured magnetic field will be compared and discussed.
Date: April 20, 1999
Creator: Dejus, R. J.
Object Type: Article
System: The UNT Digital Library
Case studies of geophysical search methods relevant to the continuation phase of an on-Site inspection (open access)

Case studies of geophysical search methods relevant to the continuation phase of an on-Site inspection

Part II of the Protocol of the Comprehensive Test Ban Treaty prescribes the use of geophysical methods such as active seismic surveys and electrical conductivity measurements to search for and locate underground anomalies, including cavities and rubble zones, during the continuation phase of an on-site inspection. In this paper the application of spontaneous potential, magnetotelluric, active seismic, and gas sampling studies at the US Nevada Test Site associated with underground nuclear explosions will be described and discussed in the context of on-site inspections. Spontaneous potential and E-field ratio telluric methods were found to be effective in some geologic settings but not in others. An example of gas sampling is shown for which radiogenic gas was detected several years after detonation. The case study of the application of active seismic methods illustrates limitations imposed by the use of relatively simple systems in the field. Detection of a deeply-buried cavity or rubble zone will be difficult; results from the application of only a single method will likely be ambiguous. Best results will come from the synthesis of results from a number of widely-varying methods.
Date: April 20, 1999
Creator: Sweeney, J. J.
Object Type: Article
System: The UNT Digital Library
Commissioning results of the narrow-band beam position monitor system upgrade in the APS storage ring. (open access)

Commissioning results of the narrow-band beam position monitor system upgrade in the APS storage ring.

When using a low emittance storage ring as a high brightness synchrotron radiation source, it is critical to maintain a very high degree of orbit stability, both for the short term and for the duration of an operational fill. A fill-to-fill reproducibility is an additional important requirement. Recent developments in orbit correction algorithms have provided tools that are capable of achieving a high degree of orbit stability. However, the performance of these feedback systems can be severely limited if there are errors in the beam position monitors (BPMs). The present orbit measurement and correction system at the APS storage ring utilizes 360 broad-band-type BPMs that provide turn-by-turn diagnostics and an ultra-stable orbit: < 1.8 micron rms vertically and 4.5 microns rms horizontally in a frequency band of 0.017 to 30 Hz. The effects of beam intensity and bunch pattern dependency on these BPMs have been significantly reduced by employing offset compensation correction. Recently, 40 narrow-band switching-type BPMs have been installed in the APS storage ring, two in each of 20 operational insertion device straight sections, bringing the total number of beam position monitors to 400. The use of narrow-band BPM electronics is expected to reduce sensitivity to beam intensity, bunch …
Date: April 20, 1999
Creator: Singh, O.
Object Type: Article
System: The UNT Digital Library
Comparison of asymmetric with symmetric feed oil injection parameters in a riser reactor. (open access)

Comparison of asymmetric with symmetric feed oil injection parameters in a riser reactor.

A computational fluid dynamic (CFD) computer code was used to determine the effects of product yields of three feed injection parameters in a fluidized catalytic cracking (FCC) riser reactor. This study includes the effects of both symmetrical and non-symmetrical injection parameters. All these parameters have significant effects on the feed oil spray distribution, vaporization rates and the resulting product yields. This study also indicates that optimum parameter ranges exist for the investigated parameters.
Date: April 20, 1999
Creator: Bowman, B. J.; Chang, S. L.; Lottes, S. A. & Zhou, C. Q.
Object Type: Article
System: The UNT Digital Library
Computer simulation of FCC riser reactors. (open access)

Computer simulation of FCC riser reactors.

A three-dimensional computational fluid dynamics (CFD) code, ICRKFLO, was developed to simulate the multiphase reacting flow system in a fluid catalytic cracking (FCC) riser reactor. The code solve flow properties based on fundamental conservation laws of mass, momentum, and energy for gas, liquid, and solid phases. Useful phenomenological models were developed to represent the controlling FCC processes, including droplet dispersion and evaporation, particle-solid interactions, and interfacial heat transfer between gas, droplets, and particles. Techniques were also developed to facilitate numerical calculations. These techniques include a hybrid flow-kinetic treatment to include detailed kinetic calculations, a time-integral approach to overcome numerical stiffness problems of chemical reactions, and a sectional coupling and blocked-cell technique for handling complex geometry. The copyrighted ICRKFLO software has been validated with experimental data from pilot- and commercial-scale FCC units. The code can be used to evaluate the impacts of design and operating conditions on the production of gasoline and other oil products.
Date: April 20, 1999
Creator: Chang, S. L.; Golchert, B.; Lottes, S. A.; Petrick, M. & Zhou, C. Q.
Object Type: Article
System: The UNT Digital Library
Congressional Budget Act Points of Order (open access)

Congressional Budget Act Points of Order

Title III of the Congressional Budget Act (CBA) of 1974 (P.L. 93-344), as amended, establishes the points of order that are used to enforce congressional budget procedures and substantive provisions of a budget resolution. These points of order prohibit certain congressional actions and consideration of certain legislation.
Date: April 20, 1999
Creator: Heniff, Bill, Jr.
Object Type: Report
System: The UNT Digital Library
A consortium approach to glass furnace modeling. (open access)

A consortium approach to glass furnace modeling.

Using computational fluid dynamics to model a glass furnace is a difficult task for any one glass company, laboratory, or university to accomplish. The task of building a computational model of the furnace requires knowledge and experience in modeling two dissimilar regimes (the combustion space and the liquid glass bath), along with the skill necessary to couple these two regimes. Also, a detailed set of experimental data is needed in order to evaluate the output of the code to ensure that the code is providing proper results. Since all these diverse skills are not present in any one research institution, a consortium was formed between Argonne National Laboratory, Purdue University, Mississippi State University, and five glass companies in order to marshal these skills into one three-year program. The objective of this program is to develop a fully coupled, validated simulation of a glass melting furnace that may be used by industry to optimize the performance of existing furnaces.
Date: April 20, 1999
Creator: Chang, S.-L.; Golchert, B. & Petrick, M.
Object Type: Article
System: The UNT Digital Library
Construction and measurement techniques for the APS LEUTL project RF beam position monitors. (open access)

Construction and measurement techniques for the APS LEUTL project RF beam position monitors.

The design, construction, and assembly procedure of 24 rf beam position monitors used in the Advanced Photon Source low-energy undulator test line and linear accelerator (linac) are described. Beam stability as well as beam positioning capabilities are essential to the LEUTL project. A design objective of the LEUTL facility is to achieve better than 1-{micro}m resolution. The highest care was used in the mechanical fabrication and assembly of the BPM units. The latest experimental results using these BPMs are presented.
Date: April 20, 1999
Creator: Gorski, A.
Object Type: Article
System: The UNT Digital Library
Cruise Missile Inventories and NATO Attacks on Yugoslavia: Background Information (open access)

Cruise Missile Inventories and NATO Attacks on Yugoslavia: Background Information

This short report provides background information on the Air Force’s Conventional Air-Launched Cruise Missile (CALCM) and the conventionally armed version of the Navy’s Tomahawk land-attack cruise missile (TLAM).
Date: April 20, 1999
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library
Damping spurious harmonic resonances in the APS storage ring beam chamber. (open access)

Damping spurious harmonic resonances in the APS storage ring beam chamber.

The APS storage ring beam chamber has been storing the beam up to 100 mA successfully. However, in some beam chambers, spurious signals corrupted the BPM outputs. The cause of the unwanted signals was investigated, and it was found that transverse electric (TE) longitudinal harmonic resonances of the beam chamber were responsible. The beam chambers have small height in the area between the ovid beam chamber and the antechamber. The structure behaves like a ridge waveguide so that the cut-off frequency of the waveguide mode becomes lower. The pass-band then includes the frequency around 350 MHz that is important to the beam position monitors (BPMs). The spurious harmonic resonances are damped with two types of dampers to restore the useful signals of the BPMs; coaxial loop dampers and lossy ceramic slab loading are used.
Date: April 20, 1999
Creator: Kang, Y.
Object Type: Article
System: The UNT Digital Library
Department of Energy: Key Factors Underlying Security Problems at DOE Facilities (open access)

Department of Energy: Key Factors Underlying Security Problems at DOE Facilities

Testimony issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO discussed its past work involving security at Department of Energy's (DOE) facilities."
Date: April 20, 1999
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Design and construction of septum magnets at the 7-GeV APS. (open access)

Design and construction of septum magnets at the 7-GeV APS.

The mechanical design, construction, and assembly procedure of six different septum magnet designs used in the Advanced Photon Source (APS) facility will be described. This will include a positron accumulator ring (PAR) AC septum magnet, a synchrotrons thin injection septum AC thin and thick extraction septa, and storage ring AC thick and thin injection septum magnets. Design parameters, material selection, assembly procedures, and operational results will be presented.
Date: April 20, 1999
Creator: Gorski, A.
Object Type: Article
System: The UNT Digital Library
Designing Smart Health Care Technology into the Home of the Future (open access)

Designing Smart Health Care Technology into the Home of the Future

This editorial paper presents a vision for intelligent health care in the home of the future, focusing on technologies with the highest potential payoff given targeted government funding over the next ten years. A secure, plug-and-play information framework provides the starting point for identifying technologies that must be developed before home-based devices can know their context and assimilate information to support care decisions.
Date: April 20, 1999
Creator: Craft, R.L. & Warren, S.
Object Type: Article
System: The UNT Digital Library
Diffuse x-ray scattering from short-period W/C multilayers at in-plane momentum transfers 0.10-0.17 {angstrom}{sup -1}. (open access)

Diffuse x-ray scattering from short-period W/C multilayers at in-plane momentum transfers 0.10-0.17 {angstrom}{sup -1}.

X-ray scattering measurements at 10 keV from multilayers having a period of 24.8 {angstrom} and consisting of 100 W/C bilayers are reported. Specular scans revealed first-order reflectivities in the range 73.5% to 78.0% with bandpasses in the range of 1.5% to 1.7%. Total roughness (or interface grading) values deduced from fitting to the specular data only were in the range 2.5 to 3.0 {angstrom} for the last-to-grow surface of the W layers. Diffuse scattering measurements were made in a geometry that permitted investigation of in-plane momentum transfers up to 0.17 {angstrom}{sup {minus}1}. This is roughly an order of magnitude larger than is possible in conventional rocking scans. Reasonable fitting results were obtained for an in-plane correlation function that has a Fourier transform proportional to exp(-vq{sub y}{sup 2}{vert_bar}z{sub i}-z{sub j}{vert_bar}), where z{sub i}-z{sub j} is the average separation between the i{sup th} and j{sup th} interfaces and q{sub y} is the in-plane momentum transfer.
Date: April 20, 1999
Creator: Headrick, R. L.; Liu, C. L. & Macrander, A. T.
Object Type: Article
System: The UNT Digital Library
Dyson-Schwinger equations and the quark-gluon plasma. (open access)

Dyson-Schwinger equations and the quark-gluon plasma.

The authors review applications of Dyson-Schwinger equations at nonzero temperature, T, and chemical potential, {mu}, touching topics such as: deconfinement and chiral symmetry restoration; the behavior of bulk thermodynamic quantities; the (T,{mu})-dependence of hadron properties; and the possibility of diquark condensation.
Date: April 20, 1999
Creator: Roberts, C. D. & Schmidt, S.
Object Type: Article
System: The UNT Digital Library
Emergency Criteria: How Five States Budget for Uncertainty (open access)

Emergency Criteria: How Five States Budget for Uncertainty

Correspondence issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on how five states budget for uncertainty, focusing on: (1) state criteria designed to control the use of reserve emergency funds; (2) how state criteria compared with criteria being proposed at the federal level; (3) how states determined whether the criteria have been met; (4) whether state criteria contain any escape clauses; and (5) whether states' criteria are useful in controlling costs."
Date: April 20, 1999
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library

Ensemble: 1999-04-20 – NOVA

Access: Use of this item is restricted to the UNT Community
A new music concert performed at the UNT College of Music Merrill Ellis Intermedia Theater.
Date: April 20, 1999
Creator: University of North Texas. Nova.
Object Type: Sound
System: The UNT Digital Library
Environmental Protection: Allocation of Operating Expenses to Strategic Goals and Objectives (open access)

Environmental Protection: Allocation of Operating Expenses to Strategic Goals and Objectives

Correspondence issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on how the Environmental Protection Agency (EPA) distributed its fiscal year (FY) 1999 Science and Technology funds among specific objectives in its FY 2000 budget request."
Date: April 20, 1999
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Tuesday, April 20, 1999 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Tuesday, April 20, 1999

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: April 20, 1999
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History