Aging Infrastructure: Dam Safety (open access)

Aging Infrastructure: Dam Safety

To help inform discussions on the federal role in dam safety, this report provides background information on the nation’s dam safety activities and funding mechanisms.
Date: March 25, 2008
Creator: Lane, Nic
Object Type: Report
System: The UNT Digital Library
Aviation Spending Guarantee Mechanisms (open access)

Aviation Spending Guarantee Mechanisms

The report discusses the cap and penalty Era, Airport and airway safety and capacity expansion act of 1987, Current FAA Funding Guarantees and Funding guarantee options.
Date: March 25, 2008
Creator: Kirk, Robert S.
Object Type: Report
System: The UNT Digital Library
Broadband Internet Access and the Digital Divide: Federal Assistance Programs (open access)

Broadband Internet Access and the Digital Divide: Federal Assistance Programs

This report is on Broadband Internet Access and the Digital Divide: Federal Assistance Programs.
Date: March 25, 2008
Creator: Kruger, Lennard G. & Gilroy, Angele A.
Object Type: Report
System: The UNT Digital Library
Changes in Geant4 Electromagnetics from Release 4.6.1 to 4.9.1 (open access)

Changes in Geant4 Electromagnetics from Release 4.6.1 to 4.9.1

None
Date: March 25, 2008
Creator: Perl, J.
Object Type: Report
System: The UNT Digital Library
A Comparison of Radiating Divertor Behavior in Single- and Double-Null Plasmas in DIII-D (open access)

A Comparison of Radiating Divertor Behavior in Single- and Double-Null Plasmas in DIII-D

'Puff and pump' radiating divertor scenarios, applied to both upper single-null (SN) and double-null (DN) H-mode plasmas, result in a 30-60% increase in radiated power with little or no decrease in {tau}{sub E}. Argon was injected into the private flux region of the upper divertor, and plasma flow into the upper divertor was enhanced by a combination of deuterium gas puffing upstream of the divertor targets and particle pumping at the targets. For the same constant deuterium injection rate, argon penetrated the main plasma of SNs more rapidly and reached a higher steady-state concentration when the Bx{del}B-ion drift direction was toward the divertor (V{sub {del}B{up_arrow}}) rather than away from the divertor (V{sub {del}B{down_arrow}}). We also found that the initial rate at which argon accumulated inside DN plasmas was more than twice that of comparable SN plasmas having the same Bx{del}B-ion drift direction. In DNs, the radiated power was not shared equally between divertors during argon injection. Only in the divertor opposite Bx{del}B ion drift direction were both significant increases in divertor radiated power and an accumulation of argon, based on spectroscopic measurements of ArII, observed. Our data suggests that a DN shape that is biased in the direction away from …
Date: March 25, 2008
Creator: Petrie, T. W.; Brooks, N. H.; Fenstermacher, M. E.; Groth, M.; Hyatt, A. W.; Isler, R. C. et al.
Object Type: Article
System: The UNT Digital Library
DOD Personnel Clearances: Questions for the Record Related to the Quality and Timeliness of Clearances (open access)

DOD Personnel Clearances: Questions for the Record Related to the Quality and Timeliness of Clearances

Correspondence issued by the Government Accountability Office with an abstract that begins "On February 13, 2008, Mr. Jack Edwards--an Acting Director in our Defense Capabilities and Management team--testified before the subcommittee at a hearing on the Department of Defense (DOD) security clearance processes. This report responds to a Congressional request for additional information on that subject. Specifically, GAO was asked the following: (1) In the report that GAO issued today to this committee and your testimony statement, you discussed a need for more emphasis on quality in clearance products and processes. What have agencies been using as quality measures, and are they sufficient? (2) Do you believe that DOD, Office of Management and Budget (OMB), and Office of Personnel Management (OPM) have made the necessary commitment to improve the security clearance process? What steps need to be taken to ensure that on-going initiatives continue past this Administration? (3) The Intel Reform Act requires that timeliness statistics be reported to Congress. Do the timeliness statistics provide a full picture of how quickly clearances are being issued? If there are additional statistics that would add to the Congress's oversight of clearance timeliness, what types of factors should be considered in identifying additional …
Date: March 25, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Fast Diagnostic For Electrical Breakdowns In Vacuum (open access)

Fast Diagnostic For Electrical Breakdowns In Vacuum

The design of an inexpensive, small, high bandwidth diagnostic for the study of vacuum insulator flashover is described. The diagnostic is based on the principle of capacitive coupling and is commonly referred to as a D-dot probe due to its sensitivity to the changing of the electric displacement field. The principle challenge for the design proved to be meeting the required mechanical size for the application rather than bandwidth. An array of these probes was fabricated and used in an insulator test stand. Data from the test stand with detailed analysis is presented. A highlight of the application of the probes to the test stand was the ability to detect the charging of the insulator surface by UV illumination as a prelude to the insulator flashover. The abrupt change in the insulator's surface charge during the flashover was also detected.
Date: March 25, 2008
Creator: Houck, T L; Javedani, J B & Lahowe, D A
Object Type: Report
System: The UNT Digital Library
First-Year Spectroscopy for the SDSS-II Supernova Survey (open access)

First-Year Spectroscopy for the SDSS-II Supernova Survey

This paper presents spectroscopy of supernovae discovered in the first season of the Sloan Digital Sky Survey-II Supernova Survey. This program searches for and measures multi-band light curves of supernovae in the redshift range z = 0.05-0.4, complementing existing surveys at lower and higher redshifts. Our goal is to better characterize the supernova population, with a particular focus on SNe Ia, improving their utility as cosmological distance indicators and as probes of dark energy. Our supernova spectroscopy program features rapid-response observations using telescopes of a range of apertures, and provides confirmation of the supernova and host-galaxy types as well as precise redshifts. We describe here the target identification and prioritization, data reduction, redshift measurement, and classification of 129 SNe Ia, 16 spectroscopically probable SNe Ia, 7 SNe Ib/c, and 11 SNe II from the first season. We also describe our efforts to measure and remove the substantial host galaxy contamination existing in the majority of our SN spectra.
Date: March 25, 2008
Creator: Zheng, Chen; Romani, Roger W.; Sako, Masao; Marriner, John; Bassett, Bruce; Becker, Andrew et al.
Object Type: Article
System: The UNT Digital Library
Gamma-ray Albedo of Small Solar System Bodies (open access)

Gamma-ray Albedo of Small Solar System Bodies

We calculate the {gamma}-ray albedo flux from cosmic-ray (CR) interactions with the solid rock and ice in Main Belt asteroids and Kuiper Belt objects (KBOs) using the Moon as a template. We show that the {gamma}-ray albedo for the Main Belt and KBOs strongly depends on the small-body mass spectrum of each system and may be detectable by the forthcoming Gamma Ray Large Area Space Telescope (GLAST). If detected, it can be used to derive the mass spectrum of small bodies in the Main Belt and Kuiper Belt and to probe the spectrum of CR nuclei at close-to-interstellar conditions. The orbits of the Main Belt asteroids and KBOs are distributed near the ecliptic, which passes through the Galactic center and high Galactic latitudes. Therefore, the {gamma}-ray emission by the Main Belt and Kuiper Belt has to be taken into account when analyzing weak {gamma}-ray sources close to the ecliptic. The asteroid albedo spectrum also exhibits a 511 keV line due to secondary positrons annihilating in the rock. This may be an important and previously unrecognized celestial foreground for the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL) observations of the Galactic 511 keV line emission including the direction of the Galactic center. For …
Date: March 25, 2008
Creator: Moskalenko, I.V.
Object Type: Article
System: The UNT Digital Library
The Gamma-Ray Albedo of the Moon (open access)

The Gamma-Ray Albedo of the Moon

We use the GEANT4 Monte Carlo framework to calculate the {gamma}-ray albedo of the Moon due to interactions of cosmic ray (CR) nuclei with moon rock. Our calculation of the albedo spectrum agrees with the EGRET data. We show that the spectrum of {gamma}-rays from the Moon is very steep with an effective cutoff around 3-4 GeV (600 MeV for the inner part of the Moon disk) and exhibits a narrow pion-decay line at 67.5 MeV, perhaps unique in astrophysics. Apart from other astrophysical sources, the albedo spectrum of the Moon is well understood, including its absolute normalization; this makes it a useful 'standard candle' for {gamma}-ray telescopes. The steep albedo spectrum also provides a unique opportunity for energy calibration of {gamma}-ray telescopes, such as the forthcoming Gamma Ray Large Area Space Telescope (GLAST). Since the albedo flux depends on the incident CR spectrum which changes over the solar cycle, it is possible to monitor the CR spectrum using the albedo {gamma}-ray flux. Simultaneous measurements of CR proton and helium spectra by the Payload for Antimatter-Matter Exploration and Light-nuclei Astrophysics (PAMELA), and observations of the albedo {gamma}-rays by the GLAST Large Area Telescope (LAT), can be used to test the …
Date: March 25, 2008
Creator: Moskalenko, I.V.; /Stanford U., HEPL /KIPAC, Menlo Park; Porter, T.A. & /UC, Santa Cruz
Object Type: Article
System: The UNT Digital Library
Gluon scattering in N=4 super-Yang-Mills theory fromweak to strong coupling (open access)

Gluon scattering in N=4 super-Yang-Mills theory fromweak to strong coupling

I describe some recent developments in the understanding of gluon scattering amplitudes in N = 4 super-Yang-Mills theory in the large-N{sub c} limit. These amplitudes can be computed to high orders in the weak coupling expansion, and also now at strong coupling using the AdS/CFT correspondence. They hold the promise of being solvable to all orders in the gauge coupling, with the help of techniques based on integrability. They are intimately related to expectation values for polygonal Wilson loops composed of light-like segments.
Date: March 25, 2008
Creator: Dixon, Lance J.
Object Type: Article
System: The UNT Digital Library
Government Interventions in Financial Markets: Economic and Historic Analysis of Subprime Mortgage Options (open access)

Government Interventions in Financial Markets: Economic and Historic Analysis of Subprime Mortgage Options

This report summarizes and analyzes four previous government market interventions in light of current mortgage market conditions.
Date: March 25, 2008
Creator: Weiss, N. Eric
Object Type: Report
System: The UNT Digital Library
Japan’s Currency Intervention: Policy Issues. March 2008 (open access)

Japan’s Currency Intervention: Policy Issues. March 2008

This report provides an overview and analysis of Japan's official intervention into currency markets, reviews various studies on the probable effect of that intervention, examines the charge that Japan has manipulated its exchange rate as defined by the International Monetary Fund (IMF), and reviews legislation and policy options.
Date: March 25, 2008
Creator: Nanto, Dick K.
Object Type: Report
System: The UNT Digital Library
Liquefied Natural Gas (LNG) Infrastructure Security: Issues for Congress (open access)

Liquefied Natural Gas (LNG) Infrastructure Security: Issues for Congress

This report provides an overview of industry and federal activities related to LNG security. The report describes U.S. LNG infrastructure, the industry's safety record and security risks, and the industry's security initiatives since September 11, 2001. It summarizes recent changes in federal LNG and maritime security law and related changes in the security roles of federal agencies. The report discusses several policy concerns related to federal LNG security efforts: 1) public costs of marine security, 2) uncertainty regarding LNG terrorism risks, and 3) security implications of promoting U.S.-flagged LNG tankers and U.S. crews.
Date: March 25, 2008
Creator: Parfomak, Paul W.
Object Type: Report
System: The UNT Digital Library
Measurement of the Spin of the $\Xi(1530)$ Resonance (open access)

Measurement of the Spin of the $\Xi(1530)$ Resonance

The properties of the {Xi}(1530) resonance are investigated in the {Lambda}{sub c}{sup +} {yields} {Xi}{sup -}{pi}{sup +}K{sup +} decay process. The data sample was collected with the BABAR detector at the SLAC PEP-II asymmetric-energy e{sup +}e{sup -} collider operating at center of mass energies 10.58 and 10.54 GeV. The corresponding integrated luminosity is approximately 230 fb{sup -1}. The spin of the {Xi}(1530) is established to be 3/2. The existence of an S-wave amplitude in the {Xi}{sup -}{pi}{sup +} system is inferred, and its interference with the {Xi}(1530)0 amplitude provides the first clear demonstration of the Breit-Wigner phase motion expected for the {Xi}(1530). The P{sub 1}(cos {theta}{sub {Xi}{sup -}}) Legendre polynomial moment indicates the presence of a significant S-wave amplitude for {Xi}{sup -}{pi}{sup +} mass values above 1.6 GeV/c{sup 2}, and a dip in the mass distribution at approximately 1.7 GeV/c{sup 2} is interpreted as due to coherent addition of a {Xi}(1690){sup 0} contribution to this amplitude. This would imply J{sup P} = 1/2{sup -} for the {Xi}(1690). Attempts at fitting the {Xi}(1530){sup 0} lineshape yield unsatisfactory results, and this failure is attributed to interference effects associated with the amplitudes describing the K{sup +}{pi}{sup +} and/or {Xi}{sup -}K{sup +} systems.
Date: March 25, 2008
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prudent, X. et al.
Object Type: Article
System: The UNT Digital Library
Medicaid Regulation of Governmental Providers (open access)

Medicaid Regulation of Governmental Providers

None
Date: March 25, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Monodromy in the CMB: Gravity Waves and String Inflation (open access)

Monodromy in the CMB: Gravity Waves and String Inflation

None
Date: March 25, 2008
Creator: Silverstein, Eva & Westphal, Alexander
Object Type: Report
System: The UNT Digital Library
Native Hawaiian Education Act: Greater Oversight Would Increase Accountability and Enable Targeting of Funds to Areas with Greatest Need (open access)

Native Hawaiian Education Act: Greater Oversight Would Increase Accountability and Enable Targeting of Funds to Areas with Greatest Need

A letter report issued by the Government Accountability Office with an abstract that begins "The Native Hawaiian Education Act (NHEA) seeks to develop innovative educational programs to assist Native Hawaiians. The Department of Education (Education) administers NHEA and has provided grants for a wide range of activities. Education is authorized to establish a Native Hawaiian Education Council and seven island councils to help implement NHEA. To inform reauthorization, GAO was asked to analyze (1) what is known about NHEA's impact on Native Hawaiian education, (2) Education's efforts to oversee NHEA grants, and (3) the extent to which Education and the Native Hawaiian councils have fulfilled their roles and responsibilities. To do this, GAO reviewed federal laws and regulations and departmental documents, and interviewed Education officials, council members, grantees, and experts in Native Hawaiian education."
Date: March 25, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Particulate matter chemistry and dynamics in the Twilight Zone at VERTIGO ALOHA and K2 Sites (open access)

Particulate matter chemistry and dynamics in the Twilight Zone at VERTIGO ALOHA and K2 Sites

Understanding particle dynamics in the 'Twilight Zone' is critical to prediction of the ocean's carbon cycle. As part of the VERTIGO (VERtical Transformations In the Global Ocean) project, this rarely sampled regime extending from the base of the euphotic layer to 1000 m, was characterized by double-paired day/night Multiple Unit Large Volume in-situ Filtration System (MULVFS) deployments and by {approx}100 high-frequency CTD/transmissometer/turbidity sensor profiles. VERTIGO studies lasting three weeks, contrasted oligotrophic station ALOHA (22.75{sup o}N 158{sup o}W), sampled in June-July 2004, with a biologically productive location (47{sup o}N 161{sup o}E) near station K2 in the Oyashio, occupied July-August 2005. Profiles of major and minor particulate components (C{sub org}, N, P, Ca, Si, Sr, Ba, Mn) in <1, 1-51, and >51 {micro}m size fractions, in-water optics, neutrally buoyant sediment trap (NBST) fluxes, and zooplankton data were intercompared. MULVFS total C{sub org} and C-Star particle beam attenuation coefficient (C{sub P}) were consistently related at both sites with a 27 {micro}M m{sup -1} conversion factor. 26 At K2, C{sub P} profiles further showed a multitude of transient spikes throughout the water column and spike abundance profiles closely paralleled the double peaked abundance profiles of zooplankton. Also at K2, copepods contributed {approx}40% and 10%, …
Date: March 25, 2008
Creator: Bishop, James K.B. & Wood, T.J.
Object Type: Article
System: The UNT Digital Library
Passports: Current Regulations (open access)

Passports: Current Regulations

None
Date: March 25, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
A Primer on the Higher Education Act (HEA) (open access)

A Primer on the Higher Education Act (HEA)

None
Date: March 25, 2008
Creator: Naughton, Blake Alan
Object Type: Report
System: The UNT Digital Library
Quantum Operation Time Reversal (open access)

Quantum Operation Time Reversal

The dynamics of an open quantum system can be described by a quantum operation: A linear, complete positive map of operators. Here, I exhibit a compact expression for the time reversal of a quantum operation, which is closely analogous to the time reversal of a classical Markov transition matrix. Since open quantum dynamics are stochastic, and not, in general, deterministic, the time reversal is not, in general, an inversion of the dynamics. Rather, the system relaxes toward equilibrium in both the forward and reverse time directions. The probability of a quantum trajectory and the conjugate, time reversed trajectory are related by the heat exchanged with the environment.
Date: March 25, 2008
Creator: Crooks, Gavin E.
Object Type: Article
System: The UNT Digital Library
Radiological Studies for the LCLS Beam Abort System (open access)

Radiological Studies for the LCLS Beam Abort System

The Linac Coherent Light Source (LCLS), a pioneer hard x-ray free electron laser is currently under construction at the Stanford Linear Accelerator Center. It is expected that by 2009 LCLS will deliver laser pulses of unprecedented brightness and short length, which will be used in several forefront research applications. This ambitious project encompasses major design challenges to the radiation protection like the numerous sources and the number of surveyed objects. In order to sort those, the showers from various loss sources have been tracked along a detailed model covering 1/2 mile of LCLS accelerator by means of the Monte Carlo intra nuclear cascade codes FLUKA and MARS15. This article covers the FLUKA studies of heat load; prompt and residual dose and environmental impact for the LCLS beam abort system.
Date: March 25, 2008
Creator: Santana Leitner, M.; Vollaire, J. & Mao, X.S.
Object Type: Article
System: The UNT Digital Library
Renewable Energy: Background and Issues for the 110th Congress (open access)

Renewable Energy: Background and Issues for the 110th Congress

None
Date: March 25, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library