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Comparison of States' Highway Construction Costs (open access)

Comparison of States' Highway Construction Costs

Correspondence issued by the General Accounting Office with an abstract that begins "We are reporting to Congress on whether Federal Highway Administration (FHWA) data can help transportation stakeholders understand how states' costs to build, reconstruct, and maintain federally financed highways, roads, and bridges (termed "constructing highways" for this report) compare. Durig our review, we became aware of significant issues regarding the quality of the data that FHWA collects and reports, a topic also discussed in this report."
Date: November 3, 2003
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Analyzing flow patterns in unsaturated fractured rock of YuccaMountain using an integrated modeling approach (open access)

Analyzing flow patterns in unsaturated fractured rock of YuccaMountain using an integrated modeling approach

This paper presents a series of modeling investigations to characterize percolation patterns in the unsaturated zone of Yucca Mountain, Nevada, a proposed underground repository site for storing high-level radioactive waste. The investigations are conducted using a modeling approach that integrates a wide variety of moisture, pneumatic, thermal, and isotopic geochemical field data into a comprehensive three-dimensional numerical model through model calibration. This integrated modeling approach, based on a dual-continuum formulation, takes into account the coupled processes of fluid and heat flow and chemical isotopic transport in Yucca Mountain's highly heterogeneous, unsaturated fractured tuffs. In particular, the model results are examined against different types of field-measured data and used to evaluate different hydrogeological conceptual models and their effects on flow patterns in the unsaturated zone. The objective of this work to provide understanding of percolation patterns and flow behavior through the unsaturated zone, which is a crucial issue in assessing repository performance.
Date: November 3, 2003
Creator: Wu, Yu-Shu; Lu, Guoping; Zhang, Keni; Pan, Lehua & Bodvarsson,Gudmundur S.
Object Type: Article
System: The UNT Digital Library
Many amino acid substitution variants identified in DNA repair genes during human population screenings are predicted to impact protein function (open access)

Many amino acid substitution variants identified in DNA repair genes during human population screenings are predicted to impact protein function

Over 520 different amino acid substitution variants have been previously identified in the systematic screening of 91 human DNA repair genes for sequence variation. Two algorithms were employed to predict the impact of these amino acid substitutions on protein activity. Sorting Intolerant From Tolerant (SIFT) classified 226 of 508 variants (44%) as ''Intolerant''. Polymorphism Phenotyping (PolyPhen) classed 165 of 489 amino acid substitutions (34%) as ''Probably or Possibly Damaging''. Another 9-15% of the variants were classed as ''Potentially Intolerant or Damaging''. The results from the two algorithms are highly associated, with concordance in predicted impact observed for {approx}62% of the variants. Twenty one to thirty one percent of the variant proteins are predicted to exhibit reduced activity by both algorithms. These variants occur at slightly lower individual allele frequency than do the variants classified as ''Tolerant'' or ''Benign''. Both algorithms correctly predicted the impact of 26 functionally characterized amino acid substitutions in the APE1 protein on biochemical activity, with one exception. It is concluded that a substantial fraction of the missense variants observed in the general human population are functionally relevant. These variants are expected to be the molecular genetic and biochemical basis for the associations of reduced DNA repair …
Date: November 3, 2003
Creator: Xi, T; Jones, I M & Mohrenweiser, H W
Object Type: Article
System: The UNT Digital Library
An Investigation to Resolve the Interaction Between Fuel Cell, Power Conditioning System and Application Loads (open access)

An Investigation to Resolve the Interaction Between Fuel Cell, Power Conditioning System and Application Loads

Solid-Oxide Fuel Cell (SOFC) stacks respond quickly to changes in load and exhibit high part- and full-load efficiencies due to its rapid electrochemistry. However, this is not true for the thermal, mechanical, and chemical balance-of-plant subsystem (BOPS), where load-following time constants are, typically, several orders of magnitude higher. This dichotomy diminishes the reliability and performance of the electrode with increasing demand of load. Because these unwanted phenomena are not well understood, the manufacturers of SOFC use conservative schemes (such as, delayed load-following to compensate for slow BOPS response or expensive inductor filtering) to control stack responses to load variations. This limits the applicability of SOFC systems for load-varying stationary and transportation applications from a cost standpoint. Thus, a need exists for the synthesis of component- and system-level models of SOFC power-conditioning systems and the development of methodologies for investigating the system-interaction issues (which reduce the lifetime and efficiency of a SOFC) and optimizing the responses of each subsystem, leading to optimal designs of power-conditioning electronics and optimal control strategies, which mitigate the electrical-feedback effects. Equally important are ''multiresolution'' finite-element modeling and simulation studies, which can predict the impact of changes in system-level variables (e.g., current ripple and load-transients) on the …
Date: November 3, 2003
Creator: Mazumder, Sudip K.; McKintyre, Chuck; Herbison, Dan; Nelson, Doug; Haynes, Comas; Spakovsky, Michael von et al.
Object Type: Report
System: The UNT Digital Library
Modified Rate-Theory Predictions in Comparison to Microstructural Data (open access)

Modified Rate-Theory Predictions in Comparison to Microstructural Data

Standard rate theory methods have recently been combined with experimental microstructures to successfully reproduce measured swelling behavior in ternary steels around 400 C. Fit parameters have reasonable values except possibly for the recombination radius, R{sub c}, which can be larger than expected. Numerical simulations of void nucleation and growth reveal the importance additional recombination processes at unstable clusters. Such extra recombination may reduce the range of possible values for R{sub c}. A modified rate theory is presented here that includes the effect of these undetectably small defect clusters. The fit values for R{sub c} are not appreciably altered, as the modification has little effect on the model behavior in the late steady state. It slightly improves the predictions for early transient times, when the sink strength of stable voids and dislocations is relatively small. Standard rate theory successfully explains steady swelling behavior in high purity stainless steel.
Date: November 3, 2003
Creator: Surh, M. P.; Okita, T. & Wolfer, W. G.
Object Type: Article
System: The UNT Digital Library
Characterize Framework for Igneous Activity at Yucca Mountain, Nevada (open access)

Characterize Framework for Igneous Activity at Yucca Mountain, Nevada

None
Date: November 3, 2003
Creator: Perry, F.; Youngs, R. & Vogt, T.
Object Type: Report
System: The UNT Digital Library
A Polymer Membrane Containing Fe0 as a Contaminant Barrier (open access)

A Polymer Membrane Containing Fe0 as a Contaminant Barrier

A polyvinyl alcohol (PVA) membrane containing iron (Fe0) particles was developed and tested as a model barrier for contaminant containment. Carbon tetrachloride, copper (Cu2+), nitrobenzene, 4-nitroacetophenone, and chromate (CrO4 2-) were selected as model contaminants. Compared with a pure PVA membrane, the Fe0/PVA membrane can increase the breakthrough lag time for Cu2+ and carbon tetrachloride by more than 100 fold. The increase in the lag time was smaller for nitrobenzene and 4-nitroacetophenone which stoichiometrically require more iron and for which the PVA membrane has a higher permeability. The effect of Fe0 was even smaller for CrO4 2- because of its slow reaction. Forty-five percent of the iron, based on the content in the dry membrane prior to hydration, was consumed by reaction with Cu2+ and 19% by reaction with carbon tetrachloride. Similarly, 25%, 17%, and 6% of the iron was consumed by nitrobenzene, 4-nitroacetophenone, and CrO4 2-, respectively. These percentages approximately double when the loss of iron during membrane hydration is considered. The permeability of the Fe0/PVA membrane after breakthrough was within a factor of three for that of pure PVA, consistent with theory. These results suggest that polymer membranes with embedded Fe0 have potential as practical contaminant barriers.
Date: November 3, 2003
Creator: Shimotori, Tsutomu; Nuxoll, Eric E.; Cussler, Edward L. & Arnold, William A.
Object Type: Report
System: The UNT Digital Library
MEASUREMENT OF FRICTIONAL PRESSURE DIFFERENTIALS DURING A VENTILATION SURVEY (open access)

MEASUREMENT OF FRICTIONAL PRESSURE DIFFERENTIALS DURING A VENTILATION SURVEY

During the course of a ventilation survey, both airflow quantity and frictional pressure losses are measured and quantified. The measurement of airflow has been extensively studied as the vast majority of ventilation standards/regulations are tied to airflow quantity or velocity. However, during the conduct of a ventilation survey, measurement of airflow only represents half of the necessary parameters required to directly calculate the airway resistance. The measurement of frictional pressure loss is an often misunderstood and misapplied part of the ventilation survey. This paper compares the two basic methods of frictional pressure drop measurements; the barometer and the gauge and tube. Personal experiences with each method will be detailed along with the authors' opinions regarding the applicability and conditions favoring each method.
Date: November 3, 2003
Creator: B.S. Prosser, PE & I.M. Loomis, PE, PhD
Object Type: Report
System: The UNT Digital Library
IRIS Final Technical Progress Report (open access)

IRIS Final Technical Progress Report

OAK-B135 This NERI project, originally started as the Secure Transportable Autonomous Light Water Reactor (STAR-LW) and currently known as the International Reactor Innovative and Secure (IRIS) project, had the objective of investigating a novel type of water-cooled reactor to satisfy the Generation IV goals: fuel cycle sustainability, enhanced reliability and safety, and improved economics. The research objectives over the three-year (1999-2002) program were as follows: First year: Assess various design alternatives and establish main characteristics of a point design; Second year: Perform feasibility and engineering assessment of the selected design solutions; Third year: Complete reactor design and performance evaluation, including cost assessment These objectives were fully attained and actually they served to launch IRIS as a full fledged project for eventual commercial deployment. The program did not terminate in 2002 at the end of the NERI program, and has just entered in its fifth year. This has been made possible by the IRIS project participants which have grown from the original four member, two-countries team to the current twenty members, nine countries consortium. All the consortium members work under their own funding and it is estimated that the value of their in-kind contributions over the life of the project has …
Date: November 3, 2003
Creator: Carelli, M. D.
Object Type: Report
System: The UNT Digital Library
Electroweak Physics with CDF (open access)

Electroweak Physics with CDF

The CDF experiment at the Tevatron has used p{bar p} collisions at {radical}s = 1.96 TeV to perform electroweak physics measurements. A program of precision electroweak tests of SM started measuring W and Z bosons cross section using different leptonic final states, evaluating dielectron Forward-Backward Asymmetry A{sub FB} and di-boson cross section production.
Date: November 3, 2003
Creator: Sidoti, A.
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 81, No. 338, Ed. 1 Monday, November 3, 2003 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 81, No. 338, Ed. 1 Monday, November 3, 2003

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: November 3, 2003
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
FY2003 LDRD Annual Report Article (open access)

FY2003 LDRD Annual Report Article

This study proposes to deliver fundamental experimental data on the melt and phase diagrams of methane in an extended region of high pressures and temperatures. This study targets three major scientific areas: the constraint of planetary models for the outer-giant planets, discovery of exotic phases and insights for many-body intermolecular interactions of non-hard sphere and non-spherical molecules for which no reliable theory exists for these models as yet. In this study, we will adopt in situ at high pressures and temperatures by using both conventional and coherent anti-Stokes Raman spectroscopy applied to laser- or ohmic heated diamond-anvil cells. Structures of methane will be characterized by using intense, third-generation synchrotron x-ray diffraction.
Date: November 3, 2003
Creator: Park, J.; Baer, B. & Yoo, C.
Object Type: Report
System: The UNT Digital Library
Reversible n-Bit to n-Bit Integer Haar-Like Transforms (open access)

Reversible n-Bit to n-Bit Integer Haar-Like Transforms

We introduce a wavelet-like transform similar to the Haar transform, but with the properties that it packs the results into the same number of bits as the original data, and is reversible. Our method, called TLHaar, uses table lookups to replace the averaging, differencing, and bit shifting performed in a Haar IntegerWavelet Transform (IWT). TLHaar maintains the same coefficient magnitude relationships for the low- and high-pass coefficients as true Haar, but reorders them to fit into the same number of bits as the input signal, thus eliminating the sign bit that is added to the Haar IWT output coefficients. Eliminating the sign bit avoids using extra memory and speeds the transform process. We tested TLHaar on a variety of image types, and when compared to the Haar IWT TLHaar is significantly faster. For image data with lines or hard edges TLHaar coefficients compress better than those of the Haar IWT. Due to its speed TLHaar is suitable for streaming hardware implementations with fixed data sizes, such as DVI channels.
Date: November 3, 2003
Creator: Senecal, J; Duchaineau, M & Joy, K I
Object Type: Article
System: The UNT Digital Library
Pre-experiment testing of the Multi Channel Systems 16-channel preamplifier CPA16 (open access)

Pre-experiment testing of the Multi Channel Systems 16-channel preamplifier CPA16

The 16-channel preamplifier model CPA16 from Multi Channel Systems was studied. The CPA16 preamplifier/amplifier module is a candidate to be used as the preamplifiers and amplifiers for the focal plane detectors of the Mass Analyzer of Super Heavy Atoms (MASHA). The equipment used to test the CPA16, the results of testing the CPA16 with a pulser, a mixed {sup 229}Th/{sup 148}Gd source and a {sup 252}Cf source, and a summary of the results will be presented.
Date: November 3, 2003
Creator: Patin, J B; Stoyer, M A; Moody, K J & Friensehner, A V
Object Type: Report
System: The UNT Digital Library
Biologically-Induced Micropitting of Alloy 22, a Candidate Nuclear Waste Packaging Material (open access)

Biologically-Induced Micropitting of Alloy 22, a Candidate Nuclear Waste Packaging Material

The effects of potential microbiologically influenced corrosion (MIC) on candidate packaging materials for nuclear waste containment are being assessed. Coupons of Alloy 22, the outer barrier candidate for waste packaging, were exposed to a simulated, saturated repository environment (or microcosm) consisting of crushed rock (tuff) from the Yucca Mountain repository site and a continual flow of simulated groundwater for periods up to five years at room temperature and 30 C. Coupons were incubated with YM tuff under both sterile and non-sterile conditions. Surfacial analysis by scanning electron microscopy of the biotically-incubated coupons show development of both submicron-sized pinholes and pores; these features were not present on either sterile or untreated control coupons. Room temperature, biotically-incubated coupons show a wide distribution of pores covering the coupon surface, while coupons incubated at 30 C show the pores restricted to polishing ridges.
Date: November 3, 2003
Creator: Martin, S; Carrillo, C & Horn, J
Object Type: Article
System: The UNT Digital Library
Confirmed results of the 248Cm(48Ca,4n)292116 experiment (open access)

Confirmed results of the 248Cm(48Ca,4n)292116 experiment

The results of a detailed analysis performed on the data obtained in the {sup 248}Cm({sup 48}Ca,4n){sup 292}116 reaction is presented. This analysis is independent of the original data analysis performed in Dubna in which three separate decay chains were found. Each decay chain began with an evaporation residue followed by three {alpha} decays and ended in a spontaneous fission event, all correlated in time and position. The analysis presented confirms that the three events are present in the data. A summary of the three events will be given as well as a description of the analysis performed.
Date: November 3, 2003
Creator: Patin, J B; Moody, K J; Stoyer, M A; Wild, J F; Shaughnessy, D A & Stoyer, N J
Object Type: Report
System: The UNT Digital Library
Elastic and Poroelastic Analysis of Thomsen Parameters for Seismic Waves in Finely Layered VTI Media (open access)

Elastic and Poroelastic Analysis of Thomsen Parameters for Seismic Waves in Finely Layered VTI Media

None
Date: November 3, 2003
Creator: Berger, E. L.
Object Type: Article
System: The UNT Digital Library
Integrated Urban Dispersion Modeling Capability (open access)

Integrated Urban Dispersion Modeling Capability

Numerical simulations represent a unique predictive tool for developing a detailed understanding of three-dimensional flow fields and associated concentration distributions from releases in complex urban settings (Britter and Hanna 2003). The accurate and timely prediction of the atmospheric dispersion of hazardous materials in densely populated urban areas is a critical homeland and national security need for emergency preparedness, risk assessment, and vulnerability studies. The main challenges in high-fidelity numerical modeling of urban dispersion are the accurate prediction of peak concentrations, spatial extent and temporal evolution of harmful levels of hazardous materials, and the incorporation of detailed structural geometries. Current computational tools do not include all the necessary elements to accurately represent hazardous release events in complex urban settings embedded in high-resolution terrain. Nor do they possess the computational efficiency required for many emergency response and event reconstruction applications. We are developing a new integrated urban dispersion modeling capability, able to efficiently predict dispersion in diverse urban environments for a wide range of atmospheric conditions, temporal and spatial scales, and release event scenarios. This new computational fluid dynamics capability includes adaptive mesh refinement and it can simultaneously resolve individual buildings and high-resolution terrain (including important vegetative and land-use features), treat complex …
Date: November 3, 2003
Creator: Kosovic, B & Chan, S T
Object Type: Article
System: The UNT Digital Library
Preliminary results of the 249Cf + 48Ca experiment (open access)

Preliminary results of the 249Cf + 48Ca experiment

The results of a detailed analysis performed on the data obtained in the {sup 249}Cf + {sup 48}Ca bombardment is presented. This analysis is independent of the original data analysis performed in Dubna in which two possible decay chains were found. The first decay chain consisted of an evaporation residue implantation followed by two alpha decays and then a spontaneous fission. The second decay chain consisted of an evaporation residue implantation followed by an immediate spontaneous fission event. This analysis confirms that the two interesting events are present in the data. A summary of the two events will be given as well as a description of the analysis performed.
Date: November 3, 2003
Creator: Patin, J B; Moody, K J; Stoyer, M A; Wild, J F; Shaughnessy, D A & Stoyer, N J
Object Type: Report
System: The UNT Digital Library
Tobacco Price Support: An Overview of the Program (open access)

Tobacco Price Support: An Overview of the Program

None
Date: November 3, 2003
Creator: unknown
Object Type: Report
System: The UNT Digital Library
U.S. Trade Policy and Changing Domestic and Foreign Priorities: A Historical Overview (open access)

U.S. Trade Policy and Changing Domestic and Foreign Priorities: A Historical Overview

None
Date: November 3, 2003
Creator: unknown
Object Type: Report
System: The UNT Digital Library
On the Optimal Allocation of R&D Resources for Climate Change Technology Development (open access)

On the Optimal Allocation of R&D Resources for Climate Change Technology Development

While technology studies and integrated assessment models incorporating endogenous technological change have demonstrated that advancing technology is a crucial component of an optimal greenhouse gas abatement strategy, the R&D process itself has received little analytical attention. This paper presents a conceptual framework for considering and exploring the optimal allocation of R&D resources for climate change technology development. The framework is then applied to a stylized application that considers the allocation between R&D focused on resolving uncertainties about the retention of sequestration and R&D focused on improving the performance of renewable energy technologies.
Date: November 3, 2003
Creator: Blanford, G J & Clarke, L E
Object Type: Report
System: The UNT Digital Library
Space Stations (open access)

Space Stations

This report looks into Congress' continued debate regarding NASA's International Space Station (ISS) program to build a permanently-occupied space station in Earth orbit where astronauts live and conduct research. NASA expects that research performed in the near-zero gravity environment of the space station will result in new discoveries in life sciences, biomedicine, and materials sciences. Current congressional space station debate focuses on the impact of the space shuttle Columbia tragedy on the ISS program; the possibility that portions of the space station may not be built for cost reasons; and whether Russia can fulfill its commitments to ISS.
Date: November 3, 2003
Creator: Smith, Marcia S.
Object Type: Report
System: The UNT Digital Library
Oral History Interview with Richard Toler, November 3, 2003 transcript

Oral History Interview with Richard Toler, November 3, 2003

The National Museum of the Pacific War presents an oral interview with Richard G. Toler. Toler grew up in Oklahoma and enlisted in the Army Air Corps in 1940. He received his commission in 1941 and proceeded to Hickam Field attached to the 42nd Bomb Squadron, 11th Bomb Group. Toler describes the attack on Pearl Harbor and his participation in the battle. He also mentions attacking Henderson Field in a B-17 on Guadalcanal prior to the Marine landing there. Toler describes having to ditch in the ocean after the raid and being rescued. He also describes participating in the Battle of Midway. Also during the war ,Toler served as an instructo for B-17 bombers at Hobbs, New Mexico. He was there when the war ended. He stayed in the Air Force and retired as a lieutenant colonel in 1963.
Date: November 3, 2003
Creator: Toler, Richard G.
Object Type: Sound
System: The Portal to Texas History