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U.S. Infrastructure: Funding Trends and Federal Agencies' Investment Estimates (open access)

U.S. Infrastructure: Funding Trends and Federal Agencies' Investment Estimates

Testimony issued by the General Accounting Office with an abstract that begins "This testimony discusses the (1) federal government's role in ensuring a sound public infrastructure and (2) estimates of future investment requirements developed by seven federal agencies: the Appalachian Regional Commission, the Environmental Protection Agency, the Federal Aviation Administration, the Federal Highway Administration, the General Services Administration, and the U.S. Army Corps of Engineers. GAO found that the federal government exerts an important influence on infrastructure investment and development. The seven agencies GAO reviewed each estimate billions of dollars for future investment in infrastructure. The estimates focused on investment in the areas of water resources, hydropower, water supply, wastewater treatment, airports, highways, mass transit, and public buildings. Although these estimates encompass major areas of public infrastructure, they cannot be easily compared or simply "added up" to produce a national estimate of infrastructure investment needs. GAO did not independently verify the seven agencies' investment estimates, but it did rely on past reviews of these data by GAO and others that examined the soundness and completeness of the methodology and data used to develop the estimates. This testimony summarized the July 2001 report (GAO-01-835) and the February 2000 report (RCED/AIMD-00-35)."
Date: July 23, 2001
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
National Atmospheric Release Advisory Center Internet Client (NARAC I Client) On-Line Help System Documentation (open access)

National Atmospheric Release Advisory Center Internet Client (NARAC I Client) On-Line Help System Documentation

None
Date: July 23, 2001
Creator: Belles, R.; Fischer, K.; Foster, K.; Foster, C.; Gash, J. & Stewart, J.
Object Type: Text
System: The UNT Digital Library
[Letter from Daniel C. Graney to Michael Milliken] (open access)

[Letter from Daniel C. Graney to Michael Milliken]

Letter from Daniel C. Graney to Michael Milliken on July 23, 2001, discussing membership renewals with an enclosed check of $35.00. Included is an enclosed list of members with contact information.
Date: July 23, 2001
Creator: unknown
Object Type: Letter
System: The UNT Digital Library
Subsurface Contaminant Focus Area: Monitored Natural Attenuation (MNA)--Programmatic, Technical, and Regulatory Issues (open access)

Subsurface Contaminant Focus Area: Monitored Natural Attenuation (MNA)--Programmatic, Technical, and Regulatory Issues

Natural attenuation processes are commonly used for remediation of contaminated sites. A variety of natural processes occur without human intervention at all sites to varying rates and degrees of effectiveness to attenuate (decrease) the mass, toxicity, mobility, volume, or concentration of organic and inorganic contaminants in soil, groundwater, and surface water systems. The objective of this review is to identify potential technical investments to be incorporated in the Subsurface Contaminant Focus Area Strategic Plan for monitored natural attenuation. When implemented, the technical investments will help evaluate and implement monitored natural attenuation as a remediation option at DOE sites. The outcome of this review is a set of conclusions and general recommendations regarding research needs, programmatic guidance, and stakeholder issues pertaining to monitored natural attenuation for the DOE complex.
Date: July 23, 2001
Creator: Krupka, Kenneth M. & Martin, Wayne J.
Object Type: Report
System: The UNT Digital Library
Berkeley Off-line Radioisotope Generator (BORG) (open access)

Berkeley Off-line Radioisotope Generator (BORG)

Development of chemical separations for the transactinides has traditionally been performed with longer-lived tracer activities purchased commercially. With these long-lived tracers, there is always the potential problem that the tracer atoms are not always in the same chemical form as the short-lived atoms produced in on-line experiments. This problem is especially severe for elements in groups 4 and 5 of the periodic table, where hydrolysis is present. The long-lived tracers usually are stored with a complexing agent to prevent sorption or precipitation. Chemistry experiments performed with these long-lived tracers are therefore not analogous to those chemical experiments performed in on-line experiments. One way to eliminate the differences between off-line and on-line chemistry experiments is through the use of a {sup 252}Cf fission fragment collection device. A {sup 252}Cf fission fragment collection device has already been constructed [1]. This device is limited in its capabilities. A new fission fragment device would allow the study of the chemical properties of the homologues of the heaviest elements. This new device would be capable of producing fission fragments for fast gas chemistry and aqueous chemistry experiments, long-lived tracers for model system development and neutrons for neutron activation. Fission fragment activities produced in this way …
Date: July 23, 2001
Creator: Sudowe, Ralf & Patin, Joshua B.
Object Type: Report
System: The UNT Digital Library
Implications of the Drift Scale Heater Test at Yucca Mountain for Epithermal Mineralization (open access)

Implications of the Drift Scale Heater Test at Yucca Mountain for Epithermal Mineralization

An 8-year long, drift scale heater test (DST) is currently underway at the underground Exploratory Studies Facility at Yucca Mountain in Nevada. The host rock for the DST is a highly fractured, welded tuff. The rock has {approx}10% matrix porosity 90% filled with water. After a little more than two years of heating, the temperature at the drift wall reached {approx}200 C and has been maintained at that temperature for the past {approx}1.5 years. Gas and water (both vapor and liquid) have been collected from monitoring boreholes since the test began. The CO{sub 2} concentration of the gas and the isotopic compositions of the water and CO{sub 2} are measured. These data are used to constrain numerical models of coupled thermal, hydrological, and chemical processes occurring in the system. Despite obvious differences from epithermal systems (e.g., the DST is being conducted in an unsaturated system), the trends observed in the isotopic compositions of the water and CO{sub 2} have interesting implications for natural systems. In areas below boiling, the isotope ratios of the water are near that of the ambient pore water ({delta}{sup 18}O about -12{per_thousand}). Where significant amounts of vapor condensate occur (above the boiling front above the drift …
Date: July 23, 2001
Creator: Conrad, Mark E. & Sonnenthal, Eric L.
Object Type: Report
System: The UNT Digital Library
Antenna-coupled arrays of voltage-biased superconducting bolometers (open access)

Antenna-coupled arrays of voltage-biased superconducting bolometers

We report on the development of antenna-coupled Voltage-biased Superconducting Bolometers (VSBs) which use Transition-edge Sensors (TES). Antenna coupling can greatly simplify the fabrication of large multi-frequency bolometer arrays compared to horn-coupled techniques. This simplification can make it practical to implement 1000+ element arrays that fill the focal plane of mm/sub-mm wave telescopes. We have designed a prototype device with a double-slot dipole antenna, integrated band-defining filters, and a membrane-suspended bolometer. A test chip has been constructed and will be tested shortly.
Date: July 23, 2001
Creator: Myers, Michael J.; Lee, Adrian T.; Richards, P. L.; Schwan, D.; Skidmore, J. T.; Smith, A. D. et al.
Object Type: Article
System: The UNT Digital Library
BLM and the Forest Service: Federal Taxpayers Could Benefit More From Land Sales (open access)

BLM and the Forest Service: Federal Taxpayers Could Benefit More From Land Sales

A letter report issued by the General Accounting Office with an abstract that begins "Since 1781, the federal government has transferred or sold about 1.1 billion acres to nonfederal entities--such as state and local governments, businesses, nonprofit groups, and individual citizens--under various initiatives that promoted general economic development, developed transportation systems, supported public schools, and encouraged settlement of the western frontier. Today, the Bureau of Land Management (BLM) and the Forest Service administer about seventy percent of the 657 million acres that remain in federal ownership. These agencies continue to transfer and sell federal land, but under more limited circumstances. For example, a community might want to develop a public park, a nonprofit group might want land for a shooting range, or a homeowner might want to obtain clear property title after mistakenly building part of his house on federal land. During fiscal years 1991 through 2000, BLM alone was authorized by law to transfer land. BLM transferred about 79,000 acres during this period under four key statutes and received about $3 million. BLM and the Forest Service are both authorized by law to sell land and are directed by law to receive at least fair market value when they …
Date: July 23, 2001
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 79, No. 239, Ed. 1 Monday, July 23, 2001 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 79, No. 239, Ed. 1 Monday, July 23, 2001

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: July 23, 2001
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Global Static Indexing for Real-Time Exploration of Very Large Regular Grids (open access)

Global Static Indexing for Real-Time Exploration of Very Large Regular Grids

In this paper we introduce a new indexing scheme for progressive traversal and visualization of large regular grids. We demonstrate the potential of our approach by providing a tool that displays at interactive rates planar slices of scalar field data with very modest computing resources. We obtain unprecedented results both in terms of absolute performance and, more importantly, in terms of scalability. On a laptop computer we provide real time interaction with a 2048{sup 3} grid (8 Giga-nodes) using only 20MB of memory. On an SGI Onyx we slice interactively an 8192{sup 3} grid (1/2 tera-nodes) using only 60MB of memory. The scheme relies simply on the determination of an appropriate reordering of the rectilinear grid data and a progressive construction of the output slice. The reordering minimizes the amount of I/O performed during the out-of-core computation. The progressive and asynchronous computation of the output provides flexible quality/speed tradeoffs and a time-critical and interruptible user interface.
Date: July 23, 2001
Creator: Pascucci, V & Frank, R
Object Type: Article
System: The UNT Digital Library
Parallelizing a High Accuracy Hardware-Assisted Volume Renderer for Meshes with Arbitrary Polyhedra (open access)

Parallelizing a High Accuracy Hardware-Assisted Volume Renderer for Meshes with Arbitrary Polyhedra

This paper discusses our efforts to improve the performance of the high-accuracy (HIAC) volume rendering system, based on cell projection, which is used to display unstructured, scientific data sets for analysis. The parallelization of HIAC, using the pthreads and MPI API's, resulted in significant speedup, but interactive frame rates are not yet attainable for very large data sets.
Date: July 23, 2001
Creator: Bennett,J; Cook,R; Max,N; May,D & Williams,P
Object Type: Article
System: The UNT Digital Library
Damage Prediction and Estimation in Structural Mechanics Based on Data Mining (open access)

Damage Prediction and Estimation in Structural Mechanics Based on Data Mining

Damage in a material includes localized softening or cracks in a structural component due to high operational loads, or the presence of flaws in a structure due to various manufacturing processes. Methods that identify the presence, the location and the severity of damage in the structure are useful for non-destructive evaluation procedures that are typically employed in agile manufacturing and rapid prototyping systems. The current state-of-the art techniques for these inverse problems are computationally intensive or ill conditioned when insufficient data exists. Early work by a number of researchers has shown that data mining techniques can provide a potential solution to this problem. In this paper, they investigate the use of data mining techniques for predicting failure in a variety of 2D and 3D structures using artificial neural networks (ANNs) and decision trees. This work shows that if the correct features are chosen to build the model, and the model is trained on an adequate amount of data, the model can then correctly classify the failure event as well as predict location and severity of the damage in these structures.
Date: July 23, 2001
Creator: Sandhu, S S; Kanapady, R; Tamma, K K; Kamath, C & Kumar, V
Object Type: Article
System: The UNT Digital Library
Determination of an Initial Mesh Density for Finite Element Computations via Data Mining (open access)

Determination of an Initial Mesh Density for Finite Element Computations via Data Mining

Numerical analysis software packages which employ a coarse first mesh or an inadequate initial mesh need to undergo a cumbersome and time consuming mesh refinement studies to obtain solutions with acceptable accuracy. Hence, it is critical for numerical methods such as finite element analysis to be able to determine a good initial mesh density for the subsequent finite element computations or as an input to a subsequent adaptive mesh generator. This paper explores the use of data mining techniques for obtaining an initial approximate finite element density that avoids significant trial and error to start finite element computations. As an illustration of proof of concept, a square plate which is simply supported at its edges and is subjected to a concentrated load is employed for the test case. Although simplistic, the present study provides insight into addressing the above considerations.
Date: July 23, 2001
Creator: Kanapady, R; Bathina, S K; Tamma, K K; Kamath, C & Kumar, V
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 102, No. 122, Ed. 1 Monday, July 23, 2001 (open access)

Altus Times (Altus, Okla.), Vol. 102, No. 122, Ed. 1 Monday, July 23, 2001

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: July 23, 2001
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Sun (Alvin, Tex.), Vol. 110, No. 60, Ed. 1 Monday, July 23, 2001 (open access)

The Alvin Sun (Alvin, Tex.), Vol. 110, No. 60, Ed. 1 Monday, July 23, 2001

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: July 23, 2001
Creator: Schwind, Jim & Holton, Kathleen
Object Type: Newspaper
System: The Portal to Texas History
Superlow-friction carbon films for fuel system components operating in low-sulfur diesel fuels. (open access)

Superlow-friction carbon films for fuel system components operating in low-sulfur diesel fuels.

None
Date: July 23, 2001
Creator: Erdemir, A.; Kavich, J.; Woodford, J.; Ajayi, L. & Fenske, G.
Object Type: Article
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, July 23, 2001 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, July 23, 2001

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: July 23, 2001
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 86, No. 267, Ed. 1 Monday, July 23, 2001 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 86, No. 267, Ed. 1 Monday, July 23, 2001

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: July 23, 2001
Creator: Quinnelly, Lorrie J.
Object Type: Newspaper
System: The Gateway to Oklahoma History
[News Clip: Hewlett Packard Layoffs] captions transcript

[News Clip: Hewlett Packard Layoffs]

B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: July 23, 2001, 4:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
Subsurface Contaminant Focus Area: Monitored Natural Attenuation (MNA)--Programmatic, Technical, and Regulatory Issues (open access)

Subsurface Contaminant Focus Area: Monitored Natural Attenuation (MNA)--Programmatic, Technical, and Regulatory Issues

Natural attenuation processes are commonly used for remediation of contaminated sites. A variety of natural processes occur without human intervention at all sites to varying rates and degrees of effectiveness to attenuate (decrease) the mass, toxicity, mobility, volume, or concentration of organic and inorganic contaminants in soil, groundwater, and surface water systems. The objective of this review is to identify potential technical investments to be incorporated in the Subsurface Contaminant Focus Area Strategic Plan for monitored natural attenuation. When implemented, the technical investments will help evaluate and implement monitored natural attenuation as a remediation option at DOE sites. The outcome of this review is a set of conclusions and general recommendations regarding research needs, programmatic guidance, and stakeholder issues pertaining to monitored natural attenuation for the DOE complex.
Date: July 23, 2001
Creator: Krupka, Kenneth M & Martin, Wayne J
Object Type: Report
System: The UNT Digital Library
A Numerical Analysis of the Single-Well Steam Assisted Gravity Drainage (SW-SAGD) Process, SUPRI TR-124 (open access)

A Numerical Analysis of the Single-Well Steam Assisted Gravity Drainage (SW-SAGD) Process, SUPRI TR-124

Results from this study include cumulative recoveries, temperature distributions, and production rates. It was found that cyclic steaming of the reservoir offers the most favorable option for heating the near-wellbore area to create conditions that improve initial SAGD response. More favorable reservoir conditions such as low viscosity, thick oil zones, and solution gas, improved reservoir response. Under unfavorable conditions, response was limited.
Date: July 23, 2001
Creator: Elliot, K. T. & Kovscek, A. R.
Object Type: Report
System: The UNT Digital Library
High power test of the first s-band rf gun at SRRC. (open access)

High power test of the first s-band rf gun at SRRC.

We had constructed an S-band high power rf system at SRRC (Synchrotron Radiation Research Center). It will be used as a test bench of various designs of S-band rf guns. A 2856 MHz PFN (Pulse Forming Network) system was built to deliver 2 {micro}s, 40KV voltage pulse at 10Hz repetition rate for the XK-5 Klystron. As a quick start, we had fabricated a 2856MHz single cell rf gun for the high power test. The recent results are reported.
Date: July 23, 2001
Creator: Ho, C. H.; Chang, S. S.; Chiou, J. P.; Fann, C. S.; Hsu, K. T.; Hsu, S. Y. et al.
Object Type: Article
System: The UNT Digital Library
Arpes Evidence for a Quasiparticle Liquid in Overdoped Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+delta}. (open access)

Arpes Evidence for a Quasiparticle Liquid in Overdoped Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+delta}.

High resolution angle-resolved photoemission spectroscopy of highly overdoped Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} with a T{sub c} = 51K indicates that the basic transport processes in this material are fundamentally different from both the lesser doped cuprates as well as model metallic compounds. The overdoped sample has sharp ARPES peaks at the Fermi energy throughout the Brillouin zone even in the normal state, unlike the lesser-doped compounds. In particular, the spectra near ({pi},0) point show the presence of a sharp peak well above T{sub c}. The ARPES lineshapes, and thus the self energy, at a given energy are almost independent of k. Further, the quasiparticle scattering rate at the Fermi energy seems to be closely tied to direct resistivity measurements. This leads us to the conclusion that overdoped Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} is best described as a quasiparticle liquid. However, the energy dependence of the scattering rates is quite similar to that found in the lesser-doped compounds and quite different from that seen in a typical metal.
Date: July 23, 2001
Creator: Wells, B. O.; Yusof, Z.; Valla, T.; Fedorov, A. V.; Johnson, P.; Kendziora, C. et al.
Object Type: Article
System: The UNT Digital Library
Visualization of Solution Gas Drive in Viscous Oil, SUPRI TR-126 (open access)

Visualization of Solution Gas Drive in Viscous Oil, SUPRI TR-126

Several experimental studies of solution gas drive are available in this report. Almost all of the studies have used light oil. Solution gas drive behavior, especially in heavy oil reservoirs, is poorly understood. Experiments were performed in which pore-scale solution gas drive phenomena were viewed in water/carbon dioxide and viscous oil/carbon dioxide systems. A new pressure vessel was designed and constructed to house silicon-wafer micromodels that previously operated at low (<3 atm) pressure. The new apparatus is used for the visual studies. Several interesting phenomena were viewed. The repeated nucleation of gas bubbles was observed at a gas-wet site occupied by dirt. Interestingly, the dissolution of a gas bubble into the liquid phase was previously recorded at the same nucleation site. Gas bubbles in both systems grew to span one ore more pore bodies before mobilization. Liquid viscosity affected the ease with which gas bubbles coalesced. More viscous solutions result in slower rates of coalescence. The transport of solid particles on gas-liquid interfaces was also observed.
Date: July 23, 2001
Creator: George, D. S. & Kovscek, A. R.
Object Type: Report
System: The UNT Digital Library