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Supplemental Security Income: Additional Actions Needed to Reduce Program Vulnerability to Fraud and Abuse (open access)

Supplemental Security Income: Additional Actions Needed to Reduce Program Vulnerability to Fraud and Abuse

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on the Supplemental Security Income (SSI) program's vulnerability to fraud and abuse, focusing on: (1) the extent to which SSI is vulnerable to individuals who obtain eligibility by feigning disabilities with the help of middlemen and medical providers; (2) the Social Security Administration's (SSA) methods for preventing, detecting, and responding to this type of program fraud and abuse; and (3) additional strategies SSA could use to more effectively address this problem."
Date: September 15, 1999
Creator: United States. General Accounting Office.
System: The UNT Digital Library
Defense Computers: U.S. Space Command's Management of Its Year 2000 Operational Testing (open access)

Defense Computers: U.S. Space Command's Management of Its Year 2000 Operational Testing

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on the Department of Defense's management of various year 2000-related end-to-end testing activities, focusing on: (1) the U.S. Space Command's management of its end-to-end test of space control systems essential to major theater war; and (2) what the results of this test show with respect to operational risks and readiness."
Date: November 15, 1999
Creator: United States. General Accounting Office.
System: The UNT Digital Library
United Nations: Progress of Procurement Reforms (open access)

United Nations: Progress of Procurement Reforms

A chapter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on the United Nations Secretariat's efforts to reform its procurement process, focusing on: (1) the types of procurement problems that the U.N. High Level Expert Group on Procurement and U.N. audit and inspection organizations found; (2) progress on the implementation of the Expert Group's recommendations and other reforms to correct procurement-related problems; and (3) whether these actions have succeeded in achieving the objectives of procurement reform."
Date: April 15, 1999
Creator: United States. General Accounting Office.
System: The UNT Digital Library
Technical studies on a composite groundwater sample from F- and H-Area (open access)

Technical studies on a composite groundwater sample from F- and H-Area

A composite sample of groundwater from F- and H-Areas was collected by Waste Management Tech and delivered to the Savannah River Laboratory to use in preliminary experiments that would test three remediation technologies under consideration. The three technologies are pH adjustment and filtration, decontamination with a strong acid ion exchange resin, and decontamination with a chelating ion exchange resin.
Date: August 15, 1990
Creator: Bibler, J. P.
System: The UNT Digital Library
Evaluation of Gas-Reburning and Low NOx Burners on a Wall Fired Boiler (open access)

Evaluation of Gas-Reburning and Low NOx Burners on a Wall Fired Boiler

Low NO{sub x} burners operate on the principle of delayed mixing between the coal fuel and burner air, so that less NO{sub x} is formed. Gas reburning is a combustion modification technique that consists of firing 80--85 percent of the fuel corresponding to the total heat release in the lower furnace. Reduction of NO{sub x} to molecular nitrogen (N{sub 2}) is accomplished via the downstream injection of the remaining fuel requirement in the form of natural gas (which also reduces the total SO{sub x} emissions). In a third stage, burnout air is injected at the lower temperatures in the upper furnace to complete the combustion process without generating significant additional NO{sub x}. The specific goal of this project is to demonstrate NO{sub x} emission reductions of 75 percent or more as a result of combing Low NO{sub x} Burners and Gas Reburning on a utility boiler having the design characteristics mentioned above. A Host Site Agreement has been signed by EER and a utility company in the State of Colorado: Public Service Company of Colorado (Cherokee Unit No. 3, 172 MW{sub e}) front wall fired boiler near Denver.
Date: January 15, 1992
Creator: unknown
System: The UNT Digital Library
Evaluation of gas-reburning and low NO sub x burners on a wall fired boiler (open access)

Evaluation of gas-reburning and low NO sub x burners on a wall fired boiler

The primary objective of this CCT project is to evaluate the use of Gas Reburning and Low NO{sub x} Burners (GR-LNB) for NO{sub x} emission control from a wall fired boiler. It is anticipated that, if the demonstration is successful, the GR-LNB technology could become commercialized during the 1990's and will be capable of (1) achieving significant reduction in the emissions of nitrogen oxides and sulfur dioxide (another acid rain precursor) from existing facilities to minimize environmental impacts such as transboundary and interstate pollution and/or (2) providing for future energy needs in an environmentally acceptable manner. Low NO{sub x} burners are designed to delay the mixing of the coal fuel with combustion air to minimize the NO{sub x} formation. Typically, one may obtain up to 50% reduction in NO{sub x} emissions through the use of LNB. For LNB applications, the technology is developed and a number of LNB designs are commercially available.
Date: April 15, 1992
Creator: unknown
System: The UNT Digital Library
Nuclear physics at extreme energy density (open access)

Nuclear physics at extreme energy density

This report discusses topics in the following areas: QCD transport theory; minijets in hadronic and nuclear collisions; lattice gauge theory; hadronic matter and other studies; and strong electromagnetic fields. (LSP)
Date: May 15, 1992
Creator: Mueller, B.
System: The UNT Digital Library
Development and application of photosensitive device systems to studies of biological and organic materials (open access)

Development and application of photosensitive device systems to studies of biological and organic materials

This report describes progress as of the third year of a 3-year DoE grant for 1/1/92 to 12/31/92. Because this is the last year of a 3- year grant cycle, this report will summarize progress over the entire 3-year period. The overall goals of the grant are to develop novel instrumentation and techniques for the performance of biological and materials research, and especially for the development of x-ray detectors suitable for use at storage ring sources. Research progress has been excellent and the overall goals, as well as most of the specific goals have been successfully met.
Date: May 15, 1992
Creator: Gruner, S. M. & Reynolds, G. T.
System: The UNT Digital Library
Enhancing the use of coals by gas reburning-sorbent injection (open access)

Enhancing the use of coals by gas reburning-sorbent injection

The objective of this project is to evaluate and demonstrate a cost effective emission control technology for acid rain precursors, oxides of nitrogen (NO{sub x}) and sulfur (SO{sub x}), on two coal fired utility boilers in Illinois. The units selected are representative of pre-NSPS design practices: tangential and cyclone fired. Work on a third unit, wall fired, has been stopped because of funding limitations. The specific objectives are to demonstrate reductions of 60 percent in NO{sub x} and 50 percent in SO{sub x} emissions, by a combination of two developed technologies, gas reburning (GR) and sorbent injection (SI).
Date: April 15, 1992
Creator: unknown
System: The UNT Digital Library
Air gun test evaluation (open access)

Air gun test evaluation

A mechanical shock testing apparatus is used for testing the response of components subject to large accelerations in hostile environments. The test acceleration is provided by the impact of a bullet against a plate on which the component to be tested is mounted. This report describes a series of experiments that were performed to determine the dependence of the air gun test apparatus performance on incremental changes in the hardware configurations, changes in the pressure used to drive the bullet, and different accelerometers. The effect of variation of these experimental factors on the measured acceleration was determined using a Taguchi screening experimental design. Experimental settings were determined that can be used to operate the tester with a measured output within acceleration specifications.
Date: January 15, 1992
Creator: Carleton, J.J. II; Fox, L. & Rudy, C.R.
System: The UNT Digital Library
Role of structure in ion movement of glasses (open access)

Role of structure in ion movement of glasses

Can the structure of a melt much above the glass transition temperature (Tg) determine the structure and (transport) properties of glass In other words, are there extremely long lasting configurations in a melt which would affect ion transport in the glassy state A major effort during the past year has been to address these very fundamental questions. An important consideration here is to separate the effect of the variable melt structure from that of a variable cooling rate in the glass transformation range. For this reason our experiment consists of preparing 0.3 Na{sub 2}O--0.7 B{sub 2}O{sub 3} glasses from the melt which is first equilibrated at 1400 C and then annealed at 850 C for 0 to 180 minutes. From 850 C variously annealed melts are quenched to the glassy state by following identical procedure. If the structure (as reflected in ion transport) of 1400 C melt relaxes to that of 850 C in {approximately} minutes, we may expect to observe variations in the conductivity time in the ns range.
Date: January 15, 1992
Creator: Jain, Himanshu
System: The UNT Digital Library
Pyrite oxidation in saturated and Unsaturated Porous Media Flow: AComparison of alternative mathematical modeling approaches (open access)

Pyrite oxidation in saturated and Unsaturated Porous Media Flow: AComparison of alternative mathematical modeling approaches

Pyrite (FeS{sub 2}) is one of the most common naturally occurring minerals that is present in many subsurface environments. It plays an important role in the genesis of enriched ore deposits through weathering reactions, is the most abundant sulfide mineral in many mine tailings, and is the primary source of acid drainage from mines and waste rock piles. The pyrite oxidation reaction serves as a prototype for oxidative weathering processes with broad significance for geoscientific, engineering, and environmental applications. Mathematical modeling of these processes is extremely challenging because aqueous concentrations of key species vary over an enormous range, oxygen inventory and supply are typically small in comparison to pyrite inventory, and chemical reactions are complex, involving kinetic control and microbial catalysis. We present the mathematical formulation of a general multi-phase advective-diffusive reactive transport model for redox processes. Two alternative implementations were made in the TOUGHREACT and TOUGH2-CHEM simulation codes which use sequential iteration and simultaneous solution, respectively. The simulators are applied to reactive consumption of pyrite in (1) saturated flow of oxidizing water, and (2) saturated-unsaturated flow in which oxygen transport occurs in both aqueous and gas phases. Geochemical evolutions predicted from different process models are compared, and issues of …
Date: February 15, 1998
Creator: Xu, Tianfu; White, Stephen P. & Pruess, Karsten
System: The UNT Digital Library
Sealed Bid Lease Auction of Mother Earth Industries, Inc.; Geothermal Lease Holdings Located at Cove Fort - Sulphurdale, Utah (open access)
Numerical experiments on the probability of seepage intounderground openings in heterogeneous fractured rock (open access)

Numerical experiments on the probability of seepage intounderground openings in heterogeneous fractured rock

An important issue for the performance of underground nuclear waste repositories is the rate of seepage into the waste emplacement drifts. A prediction of this rate is particularly complicated for the potential repository site at Yucca Mountain, Nevada, because it is located in thick, unsaturated, fractured tuff formations. Underground opening in unsaturated media might act as capillary barriers, diverting water around them. In the present work, they study the potential rate of seepage into drifts as a function of the percolation flux at Yucca Mountain, based on a stochastic model of the fractured rock mass in the drift vicinity. A variety of flow scenarios are considered, assuming present-day and possible future climate conditions. They show that the heterogeneity in the flow domain is a key factor controlling seepage rates, since it causes channelized flow and local ponding in the unsaturated flow field.
Date: April 15, 1998
Creator: Birkholzer, J.; Li, G.; Tsang, C. F. & Tsang, Y.
System: The UNT Digital Library
[Copy of a collection of financial documents from Sharon Boyd's campaign] (open access)

[Copy of a collection of financial documents from Sharon Boyd's campaign]

Xerographic of a collection of documents reporting the handling of campaign funds for Sharon Boyd.
Date: September 15, 1992
Creator: unknown
System: The UNT Digital Library
Development and testing of industrial scale, coal fired combustion system, Phase 3 (open access)

Development and testing of industrial scale, coal fired combustion system, Phase 3

A major part of the work in this quarter was on the combustor tests in task 2. Three of the six planned tests in this task were completed. The first two were parametric tests of nominal one shift, (8 hour) duration on coal. Due to failure of the UV detector in the first test only several hours of coal fired operation were completed. In the second test, coal fired operation continued for the planned one shift until the 4 ton coal bin was empty. After reviewing this work with DOE, it was decided to focus the remaining test on longer duration operation with each test at one optimum condition. The third test was planned for two shift coal fired operation. Due to a problem with the pilot gas ignitor, combustion was delayed by 5 hours from 7 AM to Noon. As a result coal fired operation was limited to one shift between 3 PM and 11 PM. Throughout this period the combustor remained at one fixed condition with the use of computer control. Results for these three tests are presented in this report. Most of the work on the task 4 design and cost of a 20 MW combined gas-steam …
Date: February 15, 1993
Creator: Zauderer, B.
System: The UNT Digital Library
Determination of the effect of various hydrogen bonding functionalities on the viscosity of coal liquids (open access)

Determination of the effect of various hydrogen bonding functionalities on the viscosity of coal liquids

The objective of this program was to differentiate and quantitate the effects of various hydrogen bonding functionalities on the viscosity of coal liquids. Emphasis was on separating and measuring the individual effect of phenolic (acidic) and aromatic amino (basic) hydrogen bonding functionalities on the viscosity of coal liquids. The elimination of both acidic and basic hydrogen bondings was attempted by using trifluoroacetyl chloride and butyric acid in derivatization; and the elimination of basic hydrogen bondings was attempted by using only trifluoroacetyl chloride in derivatization. The selectivity toward hydrogen bondings' elimination offered by these derivatizations was proven to be feasible from a study of model compounds' derivatizations. Nine narrow-boiling-range coal distillates were obtained from distilling the coal liquids of Wilsonville Run 245 and were used as coal liquid samples. 6 figs.
Date: November 15, 1990
Creator: Wei, Jing-Fong.
System: The UNT Digital Library
FY99 Status Report on the HSV (open access)

FY99 Status Report on the HSV

'The HSV in storage in MTF has been monitored during FY99, and its overpressure has been sampled and analyzed. The HSV''s internal pressure continues to rise slowly, and the overpressure still analyzes as 100 percent 3He. The titanium tritide sample that was to be monitored annually and which had developed a leak last year has been repaired and isotherms measured. Unfortunately the sample was showing significant unexpected 3He release, so the isotherm data is corrupted by unknown levels of 3He. This release has disqualified this sample for future use, as it is now seriously divergent from the HSV material. A different sample must be selected for subsequent studies.The unexpected 3He releases of the Ti-3 sample and the possible release in other Ti samples have raised a serious issue. It should be determined why this release is occurring, so that an unexpected release of 3He during HSV unloading can be assessed as unlikely.'
Date: October 15, 1999
Creator: Shanahan, K. L.
System: The UNT Digital Library
In-beam studies of high-spin states of actinide nuclei (open access)

In-beam studies of high-spin states of actinide nuclei

High-spin states in the actinides have been studied using Coulomb- excitation, inelastic excitation reactions, and one-neutron transfer reactions. Experimental data are presented for states in {sup 232}U, {sup 233}U, {sup 234}U, {sup 235}U, {sup 238}Pu and {sup 239}Pu from a variety of reactions. Energy levels, moments-of-inertia, aligned angular momentum, Routhians, gamma-ray intensities, and cross-sections are presented for most cases. Additional spectroscopic information (magnetic moments, M{sub 1}/E{sub 2} mixing ratios, and g-factors) is presented for {sup 233}U. One- and two-neutron transfer reaction mechanisms and the possibility of band crossings (backbending) are discussed. A discussion of odd-A band fitting and Cranking calculations is presented to aid in the interpretation of rotational energy levels and alignment. In addition, several theoretical calculations of rotational populations for inelastic excitation and neutron transfer are compared to the data. Intratheory comparisons between the Sudden Approximation, Semi-Classical, and Alder-Winther-DeBoer methods are made. In connection with the theory development, the possible signature for the nuclear SQUID effect is discussed. 98 refs., 61 figs., 21 tabs.
Date: November 15, 1990
Creator: Stoyer, M.A. (Lawrence Berkeley Lab., CA (USA). Nuclear Science Div. California Univ., Berkeley, CA (USA). Dept. of Chemistry)
System: The UNT Digital Library
Cyclone performance and optimization (open access)

Cyclone performance and optimization

The objectives of this project are: to characterize the gas flow pattern within cyclones, to revise the theory for cyclone performance on the basis of these findings, and to design and test cyclones whose dimensions have been optimized using revised performance theory. This work is important because its successful completion will aid in the technology for combustion of coal in pressurized, fluidized beds. This quarter, an empirical model for predicting pressure drop across a cyclone was developed through a statistical analysis of pressure drop data for 98 cyclone designs. The model is shown to perform better than the pressure drop models of First (1950), Alexander (1949), Barth (1956), Stairmand (1949), and Shepherd-Lapple (1940). This model is used with the efficiency model of Iozia and Leith (1990) to develop an optimization curve which predicts the minimum pressure drop and the dimension rations of the optimized cyclone for a given aerodynamic cut diameter, d{sub 50}. The effect of variation in cyclone height, cyclone diameter, and flow on the optimization curve is determined. The optimization results are used to develop a design procedure for optimized cyclones. 37 refs., 10 figs., 4 tabs.
Date: September 15, 1990
Creator: Leith, D.
System: The UNT Digital Library
Positron ring system using anger-type detectors (open access)

Positron ring system using anger-type detectors

The major accomplishments of this year include (1) building and debugging a new set of coincidence electronics for our laboratory setup, (2) performing a series of detector experiments in the dry glove-box aimed at improving the performance of NaI(Tl) position-sensitive detectors, (3) modifying and debugging a Monte Carlo simulation code to test reconstruction algorithms and predict overall performance of a large solid angle PET scanner, (4) significant progress in the 3-D reprojection reconstruction algorithm and comparison to the 2-D single-slice algorithm and a 3-D multi-slice rebinning algorithm, (5) performance comparisons of the two PENN-PET scanners, which lead to a design for a large solid angle scanner with a 25-cm axial extent.
Date: November 15, 1991
Creator: Karp, J.S.
System: The UNT Digital Library
Deconvolution using a neural network (open access)

Deconvolution using a neural network

Viewing one dimensional deconvolution as a matrix inversion problem, we compare a neural network backpropagation matrix inverse with LMS, and pseudo-inverse. This is a largely an exercise in understanding how our neural network code works. 1 ref.
Date: November 15, 1990
Creator: Lehman, S.K.
System: The UNT Digital Library
Simulation studies to evaluate the effect of fracture closure on the performance of naturally fractured reservoirs (open access)

Simulation studies to evaluate the effect of fracture closure on the performance of naturally fractured reservoirs

The study has two principal objectives: (1) To evaluate the effects of fracture closure on the recovery of oil and gas reserves from naturally fractured petroleum or natural gas reservoirs. (2) To evaluate procedures for improving the recovery of these reserves using innovative fluid injection techniques to maintain reservoir pressure and mitigate the impact of fracture closure. The total scope of the study has been subdivided into three main tasks: (1) Baseline studies (non-pressure sensitive fractures); (2)studies with pressure sensitive fractures; and (3) innovative approaches for improving oil recovery.
Date: July 15, 1991
Creator: Dauben, D.L.
System: The UNT Digital Library
(Particulate Flow Research Lab) quarterly progress report, July 1, 1991--September 30, 1991 (open access)

(Particulate Flow Research Lab) quarterly progress report, July 1, 1991--September 30, 1991

Research at the Particulate Flow Research Lab continued. In the previous report it was mentioned that an anticipated change in the sphere diameter necessitated a resizing of the chute components. A check has indicated that the increased size has added enough weight to require a re-evaluation of the stresses requiring stronger fasteners. Mathematical formalism is given for the chip radiation model, and signal processing of the radiation received from the transmitting chips has been improved. A prototype apparatus has been designed and built in order to collide two identical spheres at a point in space. 4 figs.
Date: October 15, 1991
Creator: Rosato, A. D.; Dave, R. N.; Fischer, I. S. & Carr, W.
System: The UNT Digital Library