Resource Type

States

Theoretical analysis of the motions of an aircraft stabilized in roll by a displacement-response, flicker-type automatic pilot (open access)

Theoretical analysis of the motions of an aircraft stabilized in roll by a displacement-response, flicker-type automatic pilot

Report presenting a general analysis that allows the rolling motions of an aircraft using a displacement-response, flicker-type automatic pilot to be determined. The system is not ideal for many stabilization problems due to inherent residual oscillations, but it offers a simple and economical solution in situations in which steady state oscillations are not a problem. Results regarding some general remarks, transient and steady states, stabilization boundaries, amplitude equations, and period equations are provided.
Date: July 7, 1948
Creator: Curfman, Howard J., Jr. & Gardner, William N.
System: The UNT Digital Library
Study of gamma-ray strength functions (open access)

Study of gamma-ray strength functions

The use of gamma-ray strength function systematics to calculate neutron capture cross sections and capture gamma-ray spectra is discussed. The ratio of the average capture width, GAMMA/sub ..gamma../-bar, to the average level spacing, D/sub obs/, both at the neutron separation energy, can be derived from such systematics with much less uncertainty than from separate systematics for values of GAMMA/sub ..gamma../-bar and D/sub obs/. In particular, the E1 gamma-ray strength function is defined in terms of the giant dipole resonance (GDR). The GDR line shape is modeled with the usual Lorentzian function and also with a new energy-dependent, Breit-Wigner (EDBW) function. This latter form is further parameterized in terms of two overlapping resonances, even for nuclei where photonuclear measurements do not resolve two peaks. In the mass ranges studied, such modeling is successful for all nuclei away from the N = 50 closed neutron shell. Near the N = 50 shell, a one-peak EDBW appears to be more appropriate. Examples of calculated neutron capture excitation functions and capture gamma-ray spectra using the EDBW form are given for target nuclei in the mass-90 region and also in the Ta-Au mass region. 20 figures.
Date: August 7, 1980
Creator: Gardner, D. G.; Gardner, M. A. & Dietrich, F. S.
System: The UNT Digital Library
Drift waves in stellarator geometry (open access)

Drift waves in stellarator geometry

Drift waves are investigated in a real three-dimensional stellarator geometry. A linear system, based on the cold ion fluid model and a ballooning mode formalism, is solved numerically in the geometry of the stellarator H1-NF. The spectra of stable and unstable modes, as well as localization, are discussed. The dependence of the spectrum of the unstable modes on the wavevector, plasma density variation, and the location in the plasma is presented.
Date: February 7, 2000
Creator: Persson, M.; Nadeem, M.; Lewandowski, J.L.V. & Gardner, H.J.
System: The UNT Digital Library
Report of Foreign Travel of Environmental Sciences Research Staff, October 1990 (open access)

Report of Foreign Travel of Environmental Sciences Research Staff, October 1990

BIOMOVS (BIOspheric MOdel Validation Study) is an international cooperative study initiated in 1985 by the Swedish National Institute of Radiation Protection to test models designed to calculate the environmental transfer and bioaccumulation of radionuclides and other trace substances. The objective of the symposium and workshop was to synthesize results obtained during Phase 1 of BIOMOVS (the first five years of the study) and to suggest new directions that might be pursued during Phase 2 of BIOMOVS. The travelers were an instrumental part of the development of BIOMOVS. This symposium allowed the travelers to present a review of past efforts at model validation and a synthesis of current activities and to refine ideas concerning future development of models and data for assessing the fate, effect, and human risks of environmental contaminants. R. H. Gardner also visited the Free University, Amsterdam, and the National Institute of Public Health and Environmental Protection (RIVM) in Bilthoven to confer with scientists about current research in theoretical ecology and the use of models for estimating the transport and effect of environmental contaminants and to learn about the European efforts to map critical loads of acid deposition.
Date: November 7, 1990
Creator: Blaylock, B. Gordon; Hoffman, F. Owen & Gardner, Robert H.
System: The UNT Digital Library
Drift Scale THM Model (open access)

Drift Scale THM Model

This model report documents the drift scale coupled thermal-hydrological-mechanical (THM) processes model development and presents simulations of the THM behavior in fractured rock close to emplacement drifts. The modeling and analyses are used to evaluate the impact of THM processes on permeability and flow in the near-field of the emplacement drifts. The results from this report are used to assess the importance of THM processes on seepage and support in the model reports ''Seepage Model for PA Including Drift Collapse'' and ''Abstraction of Drift Seepage'', and to support arguments for exclusion of features, events, and processes (FEPs) in the analysis reports ''Features, Events, and Processes in Unsaturated Zone Flow and Transport and Features, Events, and Processes: Disruptive Events''. The total system performance assessment (TSPA) calculations do not use any output from this report. Specifically, the coupled THM process model is applied to simulate the impact of THM processes on hydrologic properties (permeability and capillary strength) and flow in the near-field rock around a heat-releasing emplacement drift. The heat generated by the decay of radioactive waste results in elevated rock temperatures for thousands of years after waste emplacement. Depending on the thermal load, these temperatures are high enough to cause boiling …
Date: October 7, 2004
Creator: Rutqvist, J.
System: The UNT Digital Library
Deregulation of natural gas: The pros and cons (open access)

Deregulation of natural gas: The pros and cons

This report discuss about the pros and cons of deregulating the natural gas.
Date: July 7, 1975
Creator: Joghn W.Jimison
System: The UNT Digital Library
Theoretical study of the tunnel-boundary lift interference due to slotted walls in the presence of the trailing-vortex system of a lifting model (open access)

Theoretical study of the tunnel-boundary lift interference due to slotted walls in the presence of the trailing-vortex system of a lifting model

Report presenting some equations that give the interference on the trailing-vortex system of a uniformly loaded finite-span wing in a circular tunnel containing partly open and partly closed walls, with special reference to symmetrical arrangements of the open and closed portions. Methods are given for extending the equations to include tunnel shapes other than circular.
Date: April 7, 1953
Creator: Matthews, Clarence W.
System: The UNT Digital Library
450/sup 0/F step transient thermal analysis of the LOFT pressurizer surge and spray line piping (open access)

450/sup 0/F step transient thermal analysis of the LOFT pressurizer surge and spray line piping

The LOFT pressurizer spray and surge line piping was analyzed for a 450/sup 0/F step change in fluid temperature. This transient was chosen to conservatively represent several pressurizer operating transients that had not previously been analyzed. These include temperature transients resulting from a 300/sup 0/F ..delta..T between pressurizer temperature and cold leg temperature, injection of a cooled (70/sup 0/F) slug of stagnant fluid into the hot (540/sup 0/F) spray line piping, and inflow of 100/sup 0/F primary coolant system water into the hot (480/sup 0/F) surge line piping.
Date: July 7, 1977
Creator: Tolan, B.J.
System: The UNT Digital Library
Stars in Photographic Emulsions Initiated by Deuterons Part II. Theoretical (open access)

Stars in Photographic Emulsions Initiated by Deuterons Part II. Theoretical

The theory of high energy nuclear stars depends on a theory of nuclear transparency and on a theory of nuclear evaporation. The transparency can be computed on the basis of a model proposed by R. Serber as soon as the interactions between the nucleons and the incident particle are known. The evaporation can be computed on the basis of the statistical model of the nucleus as soon as the nuclear entropy and binding energies of the evaporated particles are known. With approximate values for the above interactions, entropies, and binding energies, a probability distribution has been computed for the number of prongs per star. The results are in qualitative agreement with the observations on photographic emulsions described in Part 1.
Date: September 7, 1948
Creator: Horning, W. & Baumhoff, L.
System: The UNT Digital Library
Federal Land Ownership: Constitutional Authority; the History of Acquisition, Disposal, and Retention; and Current Acquisition and Disposal Authorities (open access)

Federal Land Ownership: Constitutional Authority; the History of Acquisition, Disposal, and Retention; and Current Acquisition and Disposal Authorities

Federal land ownership and management are of perennial interest to Congress. This report describes the constitutional authority for federal land ownership. It provides the history of federal land acquisition and disposal, and describes the federal land management agency jurisdictions, based on congressional authorities to reserve or withdraw lands from disposal. The report then describes several efforts to force additional federal land disposal, including recent legislative activity. It concludes with describes the various current land acquisition and disposal authorities of the four major federal land management agencies. The report will be updated to reflect major legislative activity or changes in acquisition or disposal authorities.
Date: April 7, 1999
Creator: Gorte, Ross W. & Baldwin, Pamela
System: The UNT Digital Library
Oak Ridge National Laboratory Old Hydrofracture Facility Waste Remediation Using the Borehole-Miner Extendible-Nozzle Sluicer (open access)

Oak Ridge National Laboratory Old Hydrofracture Facility Waste Remediation Using the Borehole-Miner Extendible-Nozzle Sluicer

A borehole-miner extendible-nozzle sluicing system was designed, constructed, and deployed at Oak Ridge National Laboratory to remediate five horizontal underground storage tanks containing sludge and supernate at the ORNL Old Hydrofracture Facility site. The tanks were remediated in fiscal year 1998 to remove {approx}98% of the waste, {approx}3% greater than the target removal of >95% of the waste. The tanks contained up to 18 in. of sludge covered by supernate. The 42,000 gal of low level liquid waste were estimated to contain 30,000 Ci, with 97% of this total located in the sludge. The retrieval was successful. At the completion of the remediation, the State of Tennessee Department of Environment and Conservation agreed that the tanks were cleaned to the maximum extent practicable using pumping technology. This deployment was the first radioactive demonstration of the borehole-miner extendible-nozzle water-jetting system. The extendible nozzle is based on existing bore hole-miner technology used to fracture and dislodge ore deposits in mines. Typically borehole-miner technology includes both dislodging and retrieval capabilities. Both dislodging, using the extendible-nozzle water-jetting system, and retrieval, using a jet pump located at the base of the mast, are deployed as an integrated system through one borehole or riser. Note that …
Date: October 7, 1999
Creator: Bamberger, J. A. & Boris, G. F.
System: The UNT Digital Library
Addendum to the RCRA Assessment Report for Single-Shell Tank Waste Management Area S-SX at the Hanford Site (open access)

Addendum to the RCRA Assessment Report for Single-Shell Tank Waste Management Area S-SX at the Hanford Site

The initial Resource Conservation and Recovery Act (RCRA) groundwater quality assessment report for Waste Management Area S-SX (PNNL-11810) was issued in January 1998. The report stated a plan for conducting continued assessment would be developed after addressing Washington State Department of Ecology (Ecology) comments on initial findings in PNNL-11810. Comments from Ecology were received by US Department of Energy, Richland Operations Office (DOE-RL) on September 24, 1998. Shortly thereafter, Ecology and DOE began dispute resolution and related negotiations about tank farm vadose issues. This led to proposed new Tri-Party Agreement milestones covering a RCRA Facility Investigation-Corrective Measures Study (RFI/CMS) of the four single-shell tank farm waste management areas that were in assessment status (Waste Management Areas B-BX-BY, S-SX, T and TX-TY). The RCRA Facility Investigation includes both subsurface (vadose zone and groundwater) and surface (waste handling facilities and grounds) characterization. Many of the Ecology comments on PNNL-11810 are more appropriate for, and in many cases are superseded by, the RFI/CMS at Waste Management Area S-SX. The proposed Tri-Party Agreement milestone changes that specify the scope and schedule for the RFI/CMS work plans (Tri-Party Agreement change number M-45-98-0) were issued for public comment in February 1999. The Tri-Party Agreement narrative indicates …
Date: October 7, 1999
Creator: Chou, C. J. & Johnson, V. G.
System: The UNT Digital Library
The Majorana Zero-Neutrino Double-Beta Decay Experiment White Paper (open access)

The Majorana Zero-Neutrino Double-Beta Decay Experiment White Paper

The goal of the Majorana Experiment is to determine the effective Majorana masss of the eletron neutrino. Detection of the neutrino mass implied by oscillation results in within our grasp. This exciting physics goal is best pursued using double-beta decay of germanium because of the historical and emerging advances in eliminating competing signals from radioactive backgrounds. The Majorana Experiment will consist of a large mass of 76Ge in the form of high-resolution detectors deep underground, searching for a sharp peak at the BB endpoint. We present here an overview of the entire project in order to help put in perspective the scope, the level and technial risk, and the readiness of the Collaboration to begin the undertaking.
Date: March 7, 2002
Creator: Gaitskell, R.; Barabash, A.; Konovalov, S.; Stekhanov, V.; Umatov,, V.; Brudanin, V. et al.
System: The UNT Digital Library
Speed of Presidential and Senate Actions on Supreme Court Nominations, 1900-2005 (open access)

Speed of Presidential and Senate Actions on Supreme Court Nominations, 1900-2005

This report provides information on the amount of time taken to act on all Supreme Court nominations occurring between 1900 and the present. It focuses on the actual amounts of time that Presidents and the Senate have taken to act (as opposed to the elapsed time between official points in the process).
Date: November 7, 2005
Creator: Garrett, R. Sam; Rutkus, Denis Steven & Copeland, Curtis W.
System: The UNT Digital Library
LLE Review, Quarterly Report: Volume 80, July-September 1999 (open access)

LLE Review, Quarterly Report: Volume 80, July-September 1999

This volume of the LLE Review, covering the period July-September 1999, features a theoretical analysis of a process that generates mass perturbations of an imploding target driven by modulated laser illumination. The process, referred to as laser imprint, impacts the integrity of the shell during direct-drive implosions, potentially quenching target performance. In this article V. N. Goncharov, J. A. Delettrez, S. Skupsky, and R. P. J. Town present a model of the generation of mass perturbations and analyze the mass perturbation growth due to nonuniform ablation pressure. Stabilizing mechanisms of thermal conduction smoothing and mass ablation are shown to suppress the acceleration perturbation, and mass ablation is also shown to impact velocity perturbations. The model predicts that a direct-drive cryogenic NIF target will remain intact during the implosion when l-Thz SSD beam smoothing is used.
Date: January 7, 2000
Creator: unknown
System: The UNT Digital Library
Reviving Lending to Small Businesses and Families and the Impact of the TALF (open access)

Reviving Lending to Small Businesses and Families and the Impact of the TALF

May report of the U.S. Congressional Oversight Panel describing their activities and findings regarding consumer lending to small businesses and households through the Term Asset-Backed Securities Loan Facility program (TALF).
Date: May 7, 2009
Creator: United States. Congressional Oversight Panel.
System: The UNT Digital Library
Energetic Ion Loss Diagnostic for the Wendelstein 7-AS Stellarator (open access)

Energetic Ion Loss Diagnostic for the Wendelstein 7-AS Stellarator

A diagnostic to measure the loss of energetic ions from the Wendelstein 7-AS (W7-AS) stellarator has been built. It is capable of measuring losses of both neutral beam ions and energetic ions arising from ion cyclotron resonant heating. The probe can measure losses of both clockwise and counterclockwise-going energetic ions simultaneously, and accepts a wide range of pitch angles in both directions. Initial measurements by the diagnostic are reported.
Date: December 7, 2000
Creator: Darrow, D. S.; Werner, A. & Weller, A.
System: The UNT Digital Library
Elastic-wave radiation from spherical sources (open access)

Elastic-wave radiation from spherical sources

The radiation of spherical compressional waves from a spherical cavity in an ideal elastic solid is treated. The equations for the radiation source and field are written in terms of the reduced-displacement potential. The source equation is studied in terms of characteristic frequencies, corresponding periods and wavelengths, and damping. The field equations for the stresses, strains, radial displacement, etc., are reviewed with regard to the transitions between the near and far fields. The natural parameters for defining the dynamic source and field characteristics are 2b/R and b/a in some cases and a/R in others, where a is the compressional-wave velocity, b the shear-wave velocity, and R the cavity radius. Transient solutions for stresses, strains, radial displacement, etc., include damped sinusoidal oscillations. The initial- and final-value theorems for the Laplace transform are used to obtain solutions for tau (reduced time) ..-->.. 0 + (high-frequency, farfield) and tau ..-->.. infinity (zero-frequency, near-field). 14 figures, 4 tables.
Date: December 7, 1979
Creator: Rodean, H.C.
System: The UNT Digital Library
Studies of Ion Acoustic Decay (open access)

Studies of Ion Acoustic Decay

In this project, we advanced knowledge of Ion Acoustic Decay on several fronts. In this project, we have developed and demonstrated the capability to perform experimental and theoretical studies of the Ion Acoustic Decay Instability. We have at the same time demonstrated an improved capability to do multichannel spectroscopy and Thomson scattering. We made the first observations of the time-resolved second harmonic emission at several angles simultaneously, and the first observations of the emission both parallel and perpendicular to the electric field of the laser light. We used Thomson scattering to make the first observations of the plasma waves driven by acoustic decay in a warm plasma with long density scale lengths. We also advanced both the linear and the nonlinear theory of this instability. We are thus prepared to perform experiments to address this mechanism as needed for applications.
Date: March 7, 1994
Creator: Drake, R. P.; Bauer, B. S. & Baker, K. L.
System: The UNT Digital Library
Seepage into an Underground Opening Constructed in Unsaturated Fractured Rock Under Evaporative Conditions (open access)

Seepage into an Underground Opening Constructed in Unsaturated Fractured Rock Under Evaporative Conditions

Liquid-release tests, performed in boreholes above an underground opening constructed in unsaturated fractured rock, are used in this study to evaluate seepage into a waste emplacement drift. Evidence for the existence of a capillary barrier at the ceiling of the drift is presented, based on field observations (including spreading of the wetting front across the ceiling and water movement up fractures exposed in the ceiling before seepage begins). The capillary barrier mechanism has the potential to divert water around the opening, resulting in no seepage when the percolation flux is at or below the seepage threshold flux. Liquid-release tests are used to demonstrate that a seepage threshold exists and to measure the magnitude of the seepage threshold flux for three test zones that seeped. The seepage data are interpreted using analytical techniques to estimate the test-specific strength of the rock capillary forces ({alpha}{sup -1}) that prevent water from seeping into the drift. Evaporation increases the seepage threshold flux making it more difficult for water to seep into the drift and producing artificially inflated {alpha}{sup -1} values. With adjustments for evaporation, the minimum test-specific threshold is 1,600 mm/yr with a corresponding {alpha}{sup -1} of 0.027 m.
Date: June 7, 2001
Creator: Trautz, R. C. & Wang, Joseph S. Y.
System: The UNT Digital Library
Vendors search for viscosity sensors for in situ tank waste characterization (open access)

Vendors search for viscosity sensors for in situ tank waste characterization

This report documents the search results in identifying manufacturers who can develop viscosity sensors for in situ to waste characterization. Six companies were found that have in-process viscometers.
Date: October 7, 1994
Creator: Nguyen, Q. H.
System: The UNT Digital Library
An Introduction to Judicial Review of Federal Agency Action (open access)

An Introduction to Judicial Review of Federal Agency Action

This report provides a broad overview of the issues that may be relevant to any number of present and future challenges to agency action in federal court.
Date: December 7, 2016
Creator: Cole, Jared P.
System: The UNT Digital Library
Implementing Strategies for Drying and Pressing Wood Without Emissions Controls (open access)

Implementing Strategies for Drying and Pressing Wood Without Emissions Controls

Drying and pressing wood for the manufacture of lumber, particleboard, oriented strand board (OSB), veneer and medium density fiberboard (MDF) release volatile organic compounds (VOCs) into the atmosphere. These emissions require control equipment that are capital-intensive and consume significant quantities of natural gas and electricity. The objective of our work was to understand the mechanisms through which volatile organic compounds are generated and released and to develop simple control strategies. Of the several strategies developed, two have been implemented for OSB manufacture over the course of this study. First, it was found that increasing final wood moisture by about 2-4 percentage points reduced the dryer emissions of hazardous air pollutants by over 70%. As wood dries, the escaping water evaporatively cools the wood. This cooling tapers off wood when the wood is nearly dry and the wood temperature rises. Thermal breakdown of the wood tissue occurs and VOCs are released. Raising the final wood moisture by only a few percentage points minimizes the temperature rise and reduces emissions. Evaporative cooling also impacts has implications for VOC release from wood fines. Flaking wood for OSB manufacture inevitable generates fines. Fines dry out rapidly because of their high surface area and evaporative …
Date: September 7, 2007
Creator: Banerjee, Sujit & Conners, Terrance
System: The UNT Digital Library
Stress analysis of the LOFT core barrel for LOCA + SSE loads (open access)

Stress analysis of the LOFT core barrel for LOCA + SSE loads

The results of a dynamic analysis of the LOFT Reactor Core Barrel for faulted conditions are presented in this report. Loading conditions considered were seismic accelerations resulting from a Safe Shutdown Earthquake (SSE) and pressure loadings from both a hot leg and a cold leg Loss-of-Coolant Accident (LOCA) break. Maximum stresses in the core barrel, resulting from these conditions, are presented with comparisons to Code allowables. Stresses were found to be within allowables for the faulted condition as defined in the ASME Code (1977), Appendix F.
Date: July 7, 1978
Creator: Blandford, R.K.
System: The UNT Digital Library