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Airline Deregulation: Reregulating the Airline Industry Would Likely Reverse Consumer Benefits and Not Save Airline Pensions (open access)

Airline Deregulation: Reregulating the Airline Industry Would Likely Reverse Consumer Benefits and Not Save Airline Pensions

A letter report issued by the Government Accountability Office with an abstract that begins "The Airline Deregulation Act of 1978 phased out the government's control over fares and service and allowed market forces to determine the price and level of domestic airline service in the United States. The intent was to increase competition and thereby lead to lower fares and improved service. In 2005, GAO reported on the tenuous finances of some airlines that have led to bankruptcy and pension terminations, in particular among those airlines that predated deregulation (referred to as legacy airlines). The House Report accompanying the 2006 Department of Transportation (DOT) Appropriation Act expressed concern about airline pension defaults and charged GAO with analyzing the impact of reregulating the airline industry on reducing potential pension defaults by airlines. GAO subsequently agreed to address the pension issue within a broad assessment of the airline industry since deregulation. Specifically, GAO is reporting on, among other things, (1) broad airline industry changes since deregulation, (2) fare and service changes since deregulation, and (3) whether there is evidence that reregulation of entry and fares would benefit consumers or the airline industry, or save airline pensions. DOT agreed with the conclusions in …
Date: June 9, 2006
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Homeland Security: Contract Management and Oversight for Visitor and Immigrant Status Program Need to Be Strengthened (open access)

Homeland Security: Contract Management and Oversight for Visitor and Immigrant Status Program Need to Be Strengthened

A letter report issued by the Government Accountability Office with an abstract that begins "The Department of Homeland Security (DHS) has established a multibillion-dollar program--U.S. Visitor and Immigrant Status Indicator Technology (US-VISIT)--to control and monitor the pre-entry, entry, visa status, and exit of foreign visitors. To deliver system and other program capabilities, the program relies extensively on contractors, some of whom are managed directly by US-VISIT and some by other agencies (including both DHS agencies, such as Customs and Border Protection, and non-DHS agencies, such as the General Services Administration). Because of US-VISIT's heavy reliance on contractors to deliver program capabilities, GAO was asked to determine whether DHS has established and implemented effective controls for managing and overseeing US-VISIT-related contracts."
Date: June 9, 2006
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
FBI Trilogy: Responses to Posthearing Questions (open access)

FBI Trilogy: Responses to Posthearing Questions

Correspondence issued by the Government Accountability Office with an abstract that begins "This report responds to a Congressional request for additional information related to the May 2, 2006 Congressional hearing entitled FBI Oversight. Our responses are based largely on information contained in our published report, entitled Federal Bureau of Investigation: Weak Controls over Trilogy Project Led to Payment of Questionable Contractor Costs and Missing Assets, GAO-06-306."
Date: June 9, 2006
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Using Pattern Search Methods for Surface Structure Determinationof Nanomaterials (open access)

Using Pattern Search Methods for Surface Structure Determinationof Nanomaterials

Atomic scale surface structure plays an important roleindescribing many properties of materials, especially in the case ofnanomaterials. One of the most effective techniques for surface structuredetermination is low-energy electron diffraction (LEED), which can beused in conjunction with optimization to fit simulated LEED intensitiesto experimental data. This optimization problem has a number ofcharacteristics that make it challenging: it has many local minima, theoptimization variables can be either continuous or categorical, theobjective function can be discontinuous, there are no exact analyticderivatives (and no derivatives at all for categorical variables), andfunction evaluations are expensive. In this study, we show how to apply aparticular class of optimization methods known as pattern search methodsto address these challenges. These methods donot explicitly usederivatives, and are particularly appropriate when categorical variablesare present, an important feature that has not been addressed in previousLEED studies. We have found that pattern search methods can produceexcellent results, compared to previously used methods, both in terms ofperformance and locating optimal results.
Date: June 9, 2006
Creator: Zhao, Zhengji; Meza, Juan & Van Hove, Michel
Object Type: Article
System: The UNT Digital Library
Grand Unification as a Bridge Between String Theory and Phenomenology (open access)

Grand Unification as a Bridge Between String Theory and Phenomenology

In the first part of the talk, I explain what empirical evidence points to the need for having an effective grand unification-like symmetry possessing the symmetry SU(4)-color in 4D. If one assumes the premises of a future predictive theory including gravity--be it string/M theory or a reincarnation--this evidence then suggests that such a theory should lead to an effective grand unification-like symmetry as above in 4D, near the string-GUT-scale, rather than the standard model symmetry. Advantages of an effective supersymmetric G(224) = SU(2){sub L} x SU(2){sub R} x SU(4){sup c} or SO(10) symmetry in 4D in explaining (1) observed neutrino oscillations, (2) baryogenesis via leptogenesis, and (3) certain fermion mass-relations are noted. And certain distinguishing tests of a SUSY G(224) or SO(10)-framework involving CP and flavor violations (as in {mu} {yields} e{gamma}, {tau} {yields} {mu}{gamma}, edm's of the neutron and the electron) as well as proton decay are briefly mentioned. Recalling some of the successes we have had in our understanding of nature so far, and the current difficulties of string/M theory as regards the large multiplicity of string vacua, some comments are made on the traditional goal of understanding vis a vis the recently evolved view of landscape and …
Date: June 9, 2006
Creator: Pati, Jogesh C.
Object Type: Article
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 37, No. 214, Ed. 1 Friday, June 9, 2006 (open access)

Greensheet (Houston, Tex.), Vol. 37, No. 214, Ed. 1 Friday, June 9, 2006

Free weekly newspaper that includes business and classified advertising.
Date: June 9, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 37, No. 216, Ed. 1 Friday, June 9, 2006 (open access)

Greensheet (Houston, Tex.), Vol. 37, No. 216, Ed. 1 Friday, June 9, 2006

Free weekly newspaper that includes business and classified advertising.
Date: June 9, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Dallas Voice (Dallas, Tex.), Vol. 23, No. 04, Ed. 1 Friday, June 9, 2006 (open access)

Dallas Voice (Dallas, Tex.), Vol. 23, No. 04, Ed. 1 Friday, June 9, 2006

Weekly newspaper from Dallas, Texas that includes local, state, and national news and advertising of interest to the Lesbian, Gay, Bisexual, and Transgender (LGBT) community.
Date: June 9, 2006
Creator: Vercher, Dennis
Object Type: Newspaper
System: The UNT Digital Library
U.S. and Coalition Military Operations in Afghanistan: Issues for Congress (open access)

U.S. and Coalition Military Operations in Afghanistan: Issues for Congress

None
Date: June 9, 2006
Creator: unknown
Object Type: Report
System: The UNT Digital Library
[Texas Stonewall Democratic Caucus 2006-2008 Executive Committee] (open access)

[Texas Stonewall Democratic Caucus 2006-2008 Executive Committee]

Texas Stonewall Democratic Caucus 2006 through 2008 Executive Committee list of contact information, club information, and website links.
Date: June 9, 2006
Creator: unknown
Object Type: Text
System: The UNT Digital Library
[Cost of T-shirts] (open access)

[Cost of T-shirts]

Handwritten notes on a piece of scrap paper on orders for t-shirts and hats with an amount. Two receipts listing prices of $220.00. Included is another handwritten notes with two columns listing receipts and deposit. There is a payment record of a total of $4,906.00.
Date: [2006-06-09..2006-06-10]
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 37, No. 215, Ed. 1 Friday, June 9, 2006 (open access)

Greensheet (Houston, Tex.), Vol. 37, No. 215, Ed. 1 Friday, June 9, 2006

Free weekly newspaper that includes business and classified advertising.
Date: June 9, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
STOMP Subsurface Transport Over Multiple Phases, Version 4.0, User’s Guide (open access)

STOMP Subsurface Transport Over Multiple Phases, Version 4.0, User’s Guide

This guide describes the general use, input file formatting, compilation and execution of the STOMP (Subsurface Transport Over Multiple Phases) simulator, a scientific tool for analyzing single and multiple phase subsurface flow and transport. A description of the simulator’s governing equations, constitutive functions and numerical solution algorithms are provided in a companion theory guide. In writing these guides for the STOMP simulator, the authors have assumed that the reader comprehends concepts and theories associated with multiple-phase hydrology, heat transfer, thermodynamics, radioactive chain decay, and relative permeability-saturation-capillary pressure constitutive relations. The authors further assume that the reader is familiar with the computing environment on which they plan to compile and execute the STOMP simulator. Source codes for the sequential versions of the simulator are available in pure FORTRAN 77 or mixed FORTRAN 77/90 forms. The pure FORTRAN 77 source code form requires a parameters file to define the memory requirements for the array elements. The mixed FORTRAN 77/90 form of the source code uses dynamic memory allocation to define memory requirements, based on a FORTRAN 90 preprocessor STEP, that reads the input files. The simulator utilizes a variable source code configuration, which allows the execution memory and speed to be tailored …
Date: June 9, 2006
Creator: White, Mark D. & Oostrom, Martinus
Object Type: Report
System: The UNT Digital Library
ParaDiS on Blue Gene/L: stepping up to the challenge (open access)

ParaDiS on Blue Gene/L: stepping up to the challenge

This paper reports on the efforts to enable fully scalable simulations of Dislocation Line Dynamics (DLD) for direct calculations of strength of crystalline materials. DLD simulations are challenging and do not lend themselves naturally to parallel computing. Through a combinations of novel physical approaches, mathematical algorithms and computational science developments, a new DLD code ParaDiS is shown to take meaningful advantage of BG/L and, by doing so, to enable discovery class science by computation.
Date: June 9, 2006
Creator: Hommes, Gregg; Arsenlis, Athanasios; Bulatov, Vasily; Cai, Wei; Cook, Richard; Hiratani, Masato et al.
Object Type: Article
System: The UNT Digital Library
Examination of Corrosion Products and the Alloy Surface After Crevice Corrosion of a Ni-Cr-Mo- Alloy (open access)

Examination of Corrosion Products and the Alloy Surface After Crevice Corrosion of a Ni-Cr-Mo- Alloy

The objective of this study is to investigate the composition of corrosion products and the metal surface within a crevice after localized corrosion. The analysis provides insight into the propagation, stifling and arrest processes for crevice corrosion and is part of a program to analyze the evolution of localized corrosion damage over long periods of time, i.e. 10,000 years and longer. The approach is to force the initiation of crevice corrosion by applying anodic polarization to a multiple crevice assembly (MCA). Results are reported here for alloy C-22, a Ni-Cr-Mo alloy, exposed to a high temperature, concentrated chloride solution. Controlled crevice corrosion tests were performed on C-22 under highly aggressive, accelerated condition, i.e. 4M NaCl, 100 C and anodic polarization to -0.15V-SCE. The crevice contacts were by either a polymer tape (PTFE) compressed by a ceramic former or by a polymer (PTFE) crevice former. Figure 1 shows the polarization current during a crevice corrosion test. After an incubation period, several initiation-stifle-arrest events were indicated. The low current at the end of the test indicated that the metal surface had repassivated.
Date: June 9, 2006
Creator: Shan, X. & Payer, J.H.
Object Type: Report
System: The UNT Digital Library
Ground State Quarkonium Spectral Functions Above Deconfinement. (open access)

Ground State Quarkonium Spectral Functions Above Deconfinement.

We discuss the temperature-dependence of S-wave quarkonium spectral functions in a nonrelativistic Green's function approach and compare these to lattice QCD results.
Date: June 9, 2006
Creator: Mocsy, A.; Petreczky, P. & Casalderrey-Solana, J.
Object Type: Article
System: The UNT Digital Library
Ultrahigh Energy Resolution Gamma-ray Spectrometers for Precision Measurements of Uranium Enrichment (open access)

Ultrahigh Energy Resolution Gamma-ray Spectrometers for Precision Measurements of Uranium Enrichment

Superconducting Gamma-ray detectors offer an order of magnitude higher energy resolution than conventional high-purity germanium detectors. This can significantly increase the precision of non-destructive isotope analysis for nuclear samples where line overlap affects the errors of the measurement. We have developed Gamma-detectors based on superconducting molybdenum-copper sensors and bulk tin absorbers for nuclear science and national security applications. They have, depending on design, an energy resolution between {approx}50 and {approx}150 eV FWHM at {approx}100 keV. Here we apply this detector technology to the measurement of uranium isotope ratios, and discuss the trade-offs between energy resolution and quantum efficiency involved in detector design.
Date: June 9, 2006
Creator: Ali, S; Hau, I D; Niedermayr, T R & Friedrich, S
Object Type: Article
System: The UNT Digital Library
Modeling the Effects of Crevice Former, Partculates, and the Evolving Surface Profile in Crevice Corrsion (open access)

Modeling the Effects of Crevice Former, Partculates, and the Evolving Surface Profile in Crevice Corrsion

Crevice corrosion is an important mode of localized corrosion to be evaluated for the long-term performance of corrosion resistant alloys in high temperature, aqueous environments. This work focuses on the evolution of corrosion damage of Ni-Cr-Mo alloys in hot brines. For the initiation of crevice corrosion, a critical crevice chemistry must develop within the crevice to break down the passive film. The geometry of the crevice and particularly the height of the crevice gap is an important parameter, with tighter crevices being more aggressive. Crevice corrosion models mostly define a smooth walled crevice of uniform gap and do not account for the changing profile after crevice corrosion has initiated. As a complement to the earlier models of the cathodic region, they focus here on the crevice (anodic) region and apply current and potential distribution models to examine the effects of the perturbed surface topography. The analysis focuses on three related issues: (1) the effects surface roughness of the metal and the crevice former, (2) the effects of particulate within the crevice, and (3) the evolution of the crevice profile in the active, anodic region.
Date: June 9, 2006
Creator: Landau, U.; Agarwal, A. S.; Shan, X. & Payer, J. H.
Object Type: Report
System: The UNT Digital Library
Effect of Soaking in Hot Saline Solution and Humid Atmosphere on the Passive Film Behavior of a Ni-Cr-Mo Alloy (open access)

Effect of Soaking in Hot Saline Solution and Humid Atmosphere on the Passive Film Behavior of a Ni-Cr-Mo Alloy

Alloy 22, a Ni-Cr-Mo alloy, is the candidate material for fabrication of canisters for disposal of high-level and spent nuclear fuel waste in the proposed Yucca Mountain repository in Nevada. This paper investigated the passive film behavior and corrosion properties on Alloy 22 as a function of soaking in hot, saline environments and in hot, humid atmospheres. Environmental parameters include potential, temperature, pH in chloride and multi-species solutions. Hot, humid exposures are planned for temperatures up to 300 C. Soaking times are planned to extend for up to 1000 hours. This work is part of a multi-investigator study to determine the durability of passive films and localized corrosion processes in metal exposed to moist particulate and deposits. Of particular interest are the long-term stability of the passive film and the effects of soaking in aqueous solutions or hot, humid atmospheres. A combination of electrochemical methods measure changes in passive film properties, and a combination of surface analysis techniques are used to characterize the film composition and structure. Electrochemical methods include Potentiodynamic Polarization tests for the general corrosion behavior; along with Electrochemical Impedance Spectroscopy (EIS) and Mott-Schottky (M-S) analysis for electronic properties of the passive films. Alterations in the chemical composition …
Date: June 9, 2006
Creator: Pharkya, P. & Payer, J.H.
Object Type: Report
System: The UNT Digital Library
QUARKONIUM AT FINITE TEMPERATURE. (open access)

QUARKONIUM AT FINITE TEMPERATURE.

Lattice QCD studies on charmonium at finite temperature are presented After a discussion about problems for the Maximum Entropy Method applied to finite temperature lattice QCD, I show several results on charmonium spectral functions. The 'wave function' of charmonium is also discussed to study the spatial correlation between quark and anti-quark in deconfinement phase.
Date: June 9, 2006
Creator: UMEDA, T.
Object Type: Article
System: The UNT Digital Library
Formation of Primordial Stars in a Lambda-CDM Universe (open access)

Formation of Primordial Stars in a Lambda-CDM Universe

Primordial stars are formed from a chemically pristine gas consisting of hydrogen and helium. They are believed to have been born at some early epoch in the history of the Universe and to have enriched the interstellar medium with synthesized heavy elements before the emergence of ordinary stellar populations. We study the formation of the first generation of stars in the standard cold dark matter model. We follow the gravitational collapse and thermal evolution of primordial gas clouds within early cosmic structures using very high-resolution, cosmological hydrodynamic simulations. Our simulation achieves a dynamic range of {approx} 10{sup 10} in length scale. With accurate treatment of atomic and molecular physics, it allows us to study the chemo-thermal evolution of primordial gas clouds to densities up to {rho} {approx} 2 x 10{sup -8}g cm{sup -3} (n{sub H} {approx} 10{sup 16}cm{sup -3}) without assuming any a priori equation of state; a six orders of magnitudes improvement over previous three-dimensional calculations. We implement an extensive chemistry network for hydrogen, helium and deuterium. All the relevant atomic and molecular cooling and heating processes, including cooling by collision-induced continuum emission, are implemented. For calculating optically thick H{sub 2} cooling at high densities, we use the Sobolev …
Date: June 9, 2006
Creator: Yoshida, Naoki; U., /Nagoya; Omukai, Kazuyuki; /Tokyo, Astron. Observ.; Hernquist, Lars; Astrophys., /Harvard-Smithsonian Ctr. et al.
Object Type: Article
System: The UNT Digital Library
Fe Emission And Ionized Excess Absorption in the Luminous Quasar 3C109 With XMM-Newton (open access)

Fe Emission And Ionized Excess Absorption in the Luminous Quasar 3C109 With XMM-Newton

We report results from an XMM-Newton observation of the broad-line radio galaxy 3C 109 (z=0.3056). Previous ASCA data revealed the presence of a broad iron line from the accretion disc with which the XMM-Newton spectrum is fully consistent. However, although improving the ASCA constraints on the line parameters, the quality of the data is not high enough to distinguish between an untruncated accretion disc extending down to small radii close to the black hole and a scenario in which the innermost 20-30 gravitational radii are missing. For this reason, our results are model-dependent and the hard data can be modeled equally well by considering an absorption scenario in which a large column of neutral gas partially covers the X-ray continuum source. However, the absorber would have to comprise hundreds/thousands very compact clouds close to the X-ray source, which seems rather extreme a requirement. The 2-10 keV intrinsic luminosity of 3C 109 is of the order of 2-3 x 10{sup 45} erg s{sup -1} regardless of the adopted model. A recent black hole mass estimate of {approx} 2 x 10{sup 8} M{sub {circle_dot}} implies that L{sub bol}/L{sub Edd} > 1. If partial covering is excluded, the observed reflection fraction (of the …
Date: June 9, 2006
Creator: Miniutti, Giovanni; /Cambridge U., Inst. of Astron.; Ballantyne, D. R.; U., /Arizona; Allen, S. W.; /KIPAC, Menlo Park et al.
Object Type: Report
System: The UNT Digital Library
O2 Electroreduction on Ni-Cr-Mo Alloys (open access)

O2 Electroreduction on Ni-Cr-Mo Alloys

Oxygen (O{sub 2}) reduction is the most likely process for sustaining metal oxidation in air through electrochemical ''local cells'' on the metal surface. O{sub 2} reduction occurring at one surface site is the sink for electrons generated during metal oxidation at another. Metal corrosion is reduced when O{sub 2} reduction is slowed or arrested; a process that leads to ''cathodic stifling'', O{sub 2} reduction sites become alkaline through the generation of hydroxide. The O{sub 2} reduction of two Ni-Cr-Mo alloys, i.e. C22 and C276 alloys, was studied in a half-cell with aqueous KOH electrolyte to learn the behavior of the O{sub 2} reduction local cells on the passive metal surface. This is to give experimental inputs to computational methods for predicting alloy corrosion. Fresh and aged alloy metal surfaces were studied in alkaline aqueous media with and without nitrate (1M KNO{sub 3}) in the presence and absence of O{sub 2}-Alloy behavior was characterized by electrochemical impedance spectroscopy (EIS) and voltammetry with a still electrode and a rotating ring-disk electrode (RRDE). A spectroscopic graphite rod was the auxiliary electrode, and Saturated Calomel (SCE) was the reference electrode.
Date: June 9, 2006
Creator: Rogers, S. P.; Gervasio, D. F. & Payer, J. H.
Object Type: Report
System: The UNT Digital Library
On Ex Situ NMR: Developing portable low-cost and/or single sided NMR/MRI (open access)

On Ex Situ NMR: Developing portable low-cost and/or single sided NMR/MRI

Nuclear magnetic resonance spectroscopy (NMR) is of unsurpassed versatility in its ability to non-destructively probe for chemical identity. Portable, low-cost NMR sensors would enable on site identification of potentially hazardous substances, such as signatures from production of nuclear, chemical, and biological weapon agents, narcotics, explosives, toxins, and poisons. There exist however problems that need to be considered in the case of such sensors: (a) small-scale magnets produce inhomogeneous magnetic fields and therefore undesired Larmor frequency distributions that conceal much of the useful spectral information, and (b) sensitivity in most experiments decreases due to the inherently low and strongly inhomogeneous fields associated with portable instruments. Our approach is to: (a) try to improve the field of low cost magnets either with hardware (e.g. magnet design and construction of ''shim coils'') or via special pulse sequences, where the field is ''effectively shimmed'' to appear homogeneous to the sample, and (b) to use microcoils to improve sensitivity and to allow focusing in smaller regions and therefore smaller static field variations. We have been working in setting up a table top, 2-Tesla permanent Halbach magnet system for tabletop NMR. The Spectrometer console is a Tecmag Apollo, controlled by a dell notebook. Currently an external …
Date: June 9, 2006
Creator: Demas, V.; Herberg, J.; Maxwell, R.; Pines, A. & Reimer, J.
Object Type: Report
System: The UNT Digital Library