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National Airspace System: Transformation will Require Cultural Change, Balanced Funding Priorities, and Use of All Available Management Tools (open access)

National Airspace System: Transformation will Require Cultural Change, Balanced Funding Priorities, and Use of All Available Management Tools

A chapter report issued by the Government Accountability Office with an abstract that begins "The National Airspace System (NAS) is a complex network of airports, aircraft, air traffic control (ATC) facilities, employees, and pilots. The aviation industry, which depends on the NAS, contributes about 9 percent to the gross domestic product. The Federal Aviation Administration (FAA), funded through a tax-financed trust fund and General Fund appropriations, is pursuing a multibillion-dollar modernization program. Persistent cost, schedule, and/or performance shortfalls have kept this program on GAO's list of high-risk programs since 1995. GAO was asked to review the status of NAS modernization. This report addresses NAS status by identifying the challenges that FAA faces in managing (1) infrastructure, (2) human capital, and (3) financial resources."
Date: October 14, 2005
Creator: United States. Government Accountability Office.
System: The UNT Digital Library
Is Climate Change Predictable? Really? (open access)

Is Climate Change Predictable? Really?

This project is the first application of a completely different approach to climate modeling, in which new prognostic equations are used to directly compute the evolution of two-point correlations. This project addresses three questions that are critical for the credibility of the science base for climate prediction: (1) What is the variability spectrum at equilibrium? (2) What is the rate of relaxation when subjected to external perturbations? (3) Can variations due to natural processes be distinguished from those due to transient external forces? The technical approach starts with the evolution equation for the probability distribution function and arrives at a prognostic equation for ensemble-mean two-point correlations, bypassing the detailed weather calculation. This work will expand our basic understanding of the theoretical limits of climate prediction and stimulate new experiments to perform with conventional climate models. It will furnish statistical estimates that are inaccessible with conventional climate simulations and likely will raise important new questions about the very nature of climate change and about how (and whether) climate change can be predicted. Solid progress on such issues is vital to the credibility of the science base for climate change research and will provide policymakers evaluating tradeoffs among energy technology options and …
Date: November 14, 2005
Creator: Dannevik, W P & Rotman, D A
System: The UNT Digital Library
Gene Transfer & Hybridization Studies in Hyperthermophilic Species (open access)

Gene Transfer & Hybridization Studies in Hyperthermophilic Species

A. ABSTRACT The importance of lateral gene transfer (LGT) in the evolution of microbial species has become increasingly evident with each completed microbial genome sequence. Most significantly, the genome of Thermotoga maritima MSB8, a hyperthermophilic bacterium isolated by Karl Stetter and workers from Vulcano Italy in 1986, and sequenced at The Institute for Genomic Research (TIGR) in Rockville Maryland in 1999, revealed extensive LGT between % . this bacterium and members of the archaeal domain (in particular Archaeoglobus fulgidus, and Pyracoccus frcriosus species). Based on whole genome comparisons, it was estimated that 24% of the genetic information in this organism was acquired by genetic exchange with archaeal species, Independent analyses including periodicity analysis of the T. maritimu genomic DNA sequence, phylogenetic reconstruction based on genes that appear archaeal-like, and codon and amino acid usage, have provided additional evidence for LGT between T. maritima and the archaea. More recently, DiRuggiero and workers have identified a very recent LGT event between two genera of hyperthermophilic archaea, where a nearly identical DNA fragment of 16 kb in length flanked by insertion sequence (IS) elements, exists. Undoubtedly, additional examples of LGT will be identified as more microbial genomes are completed. For the present moment …
Date: October 14, 2005
Creator: Nelson, Karen E.
System: The UNT Digital Library
SRS BEDROCK PROBABILISTIC SEISMIC HAZARD ANALYSIS (PSHA) DESIGN BASIS JUSTIFICATION (U) (open access)

SRS BEDROCK PROBABILISTIC SEISMIC HAZARD ANALYSIS (PSHA) DESIGN BASIS JUSTIFICATION (U)

This represents an assessment of the available Savannah River Site (SRS) hard-rock probabilistic seismic hazard assessments (PSHAs), including PSHAs recently completed, for incorporation in the SRS seismic hazard update. The prior assessment of the SRS seismic design basis (WSRC, 1997) incorporated the results from two PSHAs that were published in 1988 and 1993. Because of the vintage of these studies, an assessment is necessary to establish the value of these PSHAs considering more recently collected data affecting seismic hazards and the availability of more recent PSHAs. This task is consistent with the Department of Energy (DOE) order, DOE O 420.1B and DOE guidance document DOE G 420.1-2. Following DOE guidance, the National Map Hazard was reviewed and incorporated in this assessment. In addition to the National Map hazard, alternative ground motion attenuation models (GMAMs) are used with the National Map source model to produce alternate hazard assessments for the SRS. These hazard assessments are the basis for the updated hard-rock hazard recommendation made in this report. The development and comparison of hazard based on the National Map models and PSHAs completed using alternate GMAMs provides increased confidence in this hazard recommendation. The alternate GMAMs are the EPRI (2004), USGS (2002) …
Date: December 14, 2005
Creator: Lee, R. C. & McHood, M. D.
System: The UNT Digital Library
Safeguards on Textile and Apparel Imports from China (open access)

Safeguards on Textile and Apparel Imports from China

None
Date: April 14, 2005
Creator: unknown
System: The UNT Digital Library
Wildfire Protection in the 108th Congress (open access)

Wildfire Protection in the 108th Congress

None
Date: January 14, 2005
Creator: Gorte, Ross W.
System: The UNT Digital Library
House Standing Committee Chairs: Rules Governing Selection Procedures (open access)

House Standing Committee Chairs: Rules Governing Selection Procedures

This report mainly discusses about the Rules Governing Selection Procedures on House Standing Committee Chairs. House rules,republican conference rules,Democratic caucus rules each detail aspect of the procedures followed in selecting standing committee chairs.
Date: July 14, 2005
Creator: Schneider, Judy
System: The UNT Digital Library
Power Marketing Administrations: Offsetting Collections in the President’s FY2006 Budget Proposal (open access)

Power Marketing Administrations: Offsetting Collections in the President’s FY2006 Budget Proposal

None
Date: March 14, 2005
Creator: unknown
System: The UNT Digital Library
Missing and Exploited Children: Overview and Policy Concerns (open access)

Missing and Exploited Children: Overview and Policy Concerns

None
Date: January 14, 2005
Creator: unknown
System: The UNT Digital Library
Wilderness Laws: Permitted and Prohibited Uses (open access)

Wilderness Laws: Permitted and Prohibited Uses

None
Date: January 14, 2005
Creator: Gorte, Ross W.
System: The UNT Digital Library
Dynamic Data-Driven Event Reconstruction for Atmospheric Releases (open access)

Dynamic Data-Driven Event Reconstruction for Atmospheric Releases

This is a collaborative LDRD Exploratory Research project involving four directorates--Energy & Environment, Engineering, NAI and Computation. The project seeks to answer the following critical questions regarding atmospheric releases--''How much material was released? When? Where? and What are the potential consequences?'' Inaccurate estimation of the source term can lead to gross errors, time delays during a crisis, and even fatalities. We are developing a capability that seamlessly integrates observational data streams with predictive models in order to provide the best possible estimates of unknown source term parameters, as well as optimal and timely situation analyses consistent with both models and data. Our approach utilizes Bayesian inference and stochastic sampling methods (Markov Chain and Sequential Monte Carlo) to reformulate the inverse problem into a solution based on efficient sampling of an ensemble of predictive simulations, guided by statistical comparisons with data. We are developing a flexible and adaptable data-driven event-reconstruction capability for atmospheric releases that provides (1) quantitative probabilistic estimates of the principal source-term parameters (e.g., the time-varying release rate and location); (2) predictions of increasing fidelity as an event progresses and additional data become available; and (3) analysis tools for sensor network design and uncertainty studies. Our computational framework incorporates …
Date: March 14, 2005
Creator: Mirin, A; Serban, R & Kosovic, B
System: The UNT Digital Library
Navy Aircraft Carriers: Proposed Retirement of USS John F. Kennedy — Issues and Options for Congress (open access)

Navy Aircraft Carriers: Proposed Retirement of USS John F. Kennedy — Issues and Options for Congress

None
Date: January 14, 2005
Creator: unknown
System: The UNT Digital Library
Republic of the Marshall Islands Changed Circumstances Petition to Congress (open access)

Republic of the Marshall Islands Changed Circumstances Petition to Congress

This report summarizes U.S. nuclear testing on the Marshall Islands, U.S. compensation efforts to date, relevant provisions in the Compact of Free Association, and the Changed Circumstances Petition. It analyzes several issues related to the personal injury, health care, and property damages claims in the Petition.
Date: March 14, 2005
Creator: Lum, Thomas; Thomas, Kenneth R.; Redhead, C. Stephen; Bearden, David M.; Holt, Mark & Lazzari, Salvatore
System: The UNT Digital Library
Evaluation of Nevada Test Site Ground Motion and Rock Property Data to Bound Ground Motions at the Yucca Mountain Repository (open access)

Evaluation of Nevada Test Site Ground Motion and Rock Property Data to Bound Ground Motions at the Yucca Mountain Repository

Yucca Mountain licensing will require estimation of ground motions from probabilistic seismic hazard analyses (PSHA) with annual probabilities of exceedance on the order of 10{sup -6} to 10{sup -7} per year or smaller, which correspond to much longer earthquake return periods than most previous PSHA studies. These long return periods for the Yucca Mountain PSHA result in estimates of ground motion that are extremely high ({approx} 10 g) and that are believed to be physically unrealizable. However, there is at present no generally accepted method to bound ground motions either by showing that the physical properties of materials cannot maintain such extreme motions, or the energy release by the source for such large motions is physically impossible. The purpose of this feasibility study is to examine recorded ground motion and rock property data from nuclear explosions to determine its usefulness for studying the ground motion from extreme earthquakes. The premise is that nuclear explosions are an extreme energy density source, and that the recorded ground motion will provide useful information about the limits of ground motion from extreme earthquakes. The data were categorized by the source and rock properties, and evaluated as to what extent non-linearity in the material has …
Date: February 14, 2005
Creator: Hutchings, L. J.; Foxall, W.; Rambo, J. & Wagoner, J. L.
System: The UNT Digital Library
EPA’s Proposed Policy on Wastewater Blending: Background and Issues (open access)

EPA’s Proposed Policy on Wastewater Blending: Background and Issues

In November 2003 the Environmental Protection Agency (EPA) proposed a policy regarding a type of wastewater treatment practice called blending. Some cities use blending to manage peak flows of water and waste into wastewater treatment plants during and after storms as a way to prevent conditions that otherwise result in raw sewage backups into homes and other buildings or overflows into nearby waters. This report provides background on blending, why and how it is practiced, EPA’s proposed policy, associated issues, and congressional interest in the topic.
Date: February 14, 2005
Creator: Copeland, Claudia
System: The UNT Digital Library
TEM verification of the <111>-type 4-arm multi-junction in [001]-Mo single crystals (open access)

TEM verification of the <111>-type 4-arm multi-junction in [001]-Mo single crystals

To investigate and verify the formation of <111>-type 4-arm multi-junction by the dislocation reaction of 1/2[111] [b1] + 1/2[{bar 1}1{bar 1}] [b2] + 1/2[{bar 1}{bar 1}1] [b3] = 1/2[{bar 1}11] [b4], which has recently been discovered through computer simulations conducted by Vasily Bulatov and his colleagues.
Date: March 14, 2005
Creator: Hsiung, L
System: The UNT Digital Library
Forest Fire/Wildfire Protection (open access)

Forest Fire/Wildfire Protection

This report provides historical background on wildfires, and describes concerns about the wildland-urban interface and about forest and rangeland health.
Date: February 14, 2005
Creator: Gorte, Ross W.
System: The UNT Digital Library
Hardrock Mining: State Regulation (open access)

Hardrock Mining: State Regulation

This report provides a survey of state laws governing these above-mentioned aspects of hardrock mining. It provides an overview of the regulation of several specific activities associated with hardrock mineral development.
Date: March 14, 2005
Creator: Flynn, Aaron M.
System: The UNT Digital Library
Tariff Modifications: Miscellaneous Duty Suspension Bills (open access)

Tariff Modifications: Miscellaneous Duty Suspension Bills

None
Date: March 14, 2005
Creator: unknown
System: The UNT Digital Library
ViSUS: Visualization Streams for Ultimate Scalability (open access)

ViSUS: Visualization Streams for Ultimate Scalability

In this project we developed a suite of progressive visualization algorithms and a data-streaming infrastructure that enable interactive exploration of scientific datasets of unprecedented size. The methodology aims to globally optimize the data flow in a pipeline of processing modules. Each module reads a multi-resolution representation of the input while producing a multi-resolution representation of the output. The use of multi-resolution representations provides the necessary flexibility to trade speed for accuracy in the visualization process. Maximum coherency and minimum delay in the data-flow is achieved by extensive use of progressive algorithms that continuously map local geometric updates of the input stream into immediate updates of the output stream. We implemented a prototype software infrastructure that demonstrated the flexibility and scalability of this approach by allowing large data visualization on single desktop computers, on PC clusters, and on heterogeneous computing resources distributed over a wide area network. When processing terabytes of scientific data, we have achieved an effective increase in visualization performance of several orders of magnitude in two major settings: (i) interactive visualization on desktop workstations of large datasets that cannot be stored locally; (ii) real-time monitoring of a large scientific simulation with negligible impact on the computing resources available. …
Date: February 14, 2005
Creator: Pascucci, V
System: The UNT Digital Library
Strontium and Actinide Separations From High Level Nuclear Waste Solutions Using Monosodium Titanate 1. Simulant Testing (open access)

Strontium and Actinide Separations From High Level Nuclear Waste Solutions Using Monosodium Titanate 1. Simulant Testing

High-level nuclear waste produced from fuel reprocessing operations at the Savannah River Site (SRS) requires pretreatment to remove {sup 137}Cs, {sup 90}Sr and alpha-emitting radionuclides (i.e., actinides) prior to disposal. Separation processes planned at SRS include caustic side solvent extraction, for {sup 137}Cs removal, and ion exchange/sorption of {sup 90}Sr and alpha-emitting radionuclides with an inorganic material, monosodium titanate (MST). The predominant alpha-emitting radionuclides in the highly alkaline waste solutions include plutonium isotopes {sup 238}Pu, {sup 239}Pu and {sup 240}Pu. This paper provides a summary of data acquired to measure the performance of MST to remove strontium and actinides from simulated waste solutions. These tests evaluated the influence of ionic strength, temperature, solution composition and the oxidation state of plutonium.
Date: April 14, 2005
Creator: Hobbs, D. T.; Barnes, M. J.; Pulmano, R. L.; Marshall, K. M.; Edwards, T. B.; Bronikowski, M. G. et al.
System: The UNT Digital Library
A Heavy Flavor Tracker for STAR (open access)

A Heavy Flavor Tracker for STAR

We propose to construct a Heavy Flavor Tracker (HFT) for the STAR experiment at RHIC. The HFT will bring new physics capabilities to STAR and it will significantly enhance the physics capabilities of the STAR detector at central rapidities. The HFT will ensure that STAR will be able to take heavy flavor data at all luminosities attainable throughout the proposed RHIC II era.
Date: March 14, 2005
Creator: Xu, Z.; Chen, Y.; Kleinfelder, S.; Koohi, A.; Li, S.; Huang, H. et al.
System: The UNT Digital Library
Towards a Unified Approach to Information Integration - A review paper on data/information fusion (open access)

Towards a Unified Approach to Information Integration - A review paper on data/information fusion

Information or data fusion of data from different sources are ubiquitous in many applications, from epidemiology, medical, biological, political, and intelligence to military applications. Data fusion involves integration of spectral, imaging, text, and many other sensor data. For example, in epidemiology, information is often obtained based on many studies conducted by different researchers at different regions with different protocols. In the medical field, the diagnosis of a disease is often based on imaging (MRI, X-Ray, CT), clinical examination, and lab results. In the biological field, information is obtained based on studies conducted on many different species. In military field, information is obtained based on data from radar sensors, text messages, chemical biological sensor, acoustic sensor, optical warning and many other sources. Many methodologies are used in the data integration process, from classical, Bayesian, to evidence based expert systems. The implementation of the data integration ranges from pure software design to a mixture of software and hardware. In this review we summarize the methodologies and implementations of data fusion process, and illustrate in more detail the methodologies involved in three examples. We propose a unified multi-stage and multi-path mapping approach to the data fusion process, and point out future prospects and …
Date: October 14, 2005
Creator: Whitney, Paul D.; Posse, Christian & Lei, Xingye C.
System: The UNT Digital Library