Partner
UNT Libraries Government Documents Department
2,547
Oklahoma Historical Society
60
National Museum of the Pacific War/Admiral Nimitz Foundation
42
UNT Libraries Special Collections
21
Sterling Municipal Library
12
Flower Mound Public Library
10
Oklahoma State Firefighters Museum
10
Carl Albert Congressional Research and Studies Center
7
Rice University Woodson Research Center
7
San Antonio Public Library
7
52 More
Collection
Office of Scientific & Technical Information Technical Reports
2,412
Texas Digital Newspaper Program
116
Congressional Research Service Reports
81
Oklahoma Digital Newspaper Program
78
Tocker Foundation Grant
54
Government Accountability Office Reports
45
National Museum of the Pacific War Oral History Collection
42
National Museum of the Pacific War Digital Archive
42
LGBT Collections
14
The Baytown Sun
12
89 More
Country
Decade
Year
Month
Day
Language
2,830 Matching Results
Results open in a new window/tab.
Results:
1 - 24 of
2,830
next
A 3-D ray-trace model for an AMR code on distributed processors
Distributed memory AMR codes provide a special challenge for laser ray-trace modeling. For RAGE we follow the energy-carrying rays through each cell, checking for crossings which require collection a new cell index (1 of 9 in 2D). Density gradients for ray deflections can be calculated 'on the fly.' Substantial excursions must be made from the legacy PIC particle area-weighting approach, but this serves as a useful 1st step. Similarly, IDL now offers a quick graphical rendering, while ENSIGHT graphics beautifully captures the 3D light refraction and deposition.
Date:
January 1, 2002
Creator:
Mason, R. J. (Rodney J.)
Object Type:
Article
System:
The UNT Digital Library
25 years of technical advances in RFQ accelerators
The radio frequency quadrupole (RFQ) accelerator began as 'The ion linear accelerator with space-uniform strong focusing' conceived by I. M. Kapchinskii and V. A. Teplyakove. In 1979, R. H. Stokes, K. R. Crandall, J. E. Stovall and D. A. Swenson gave this concept the name RFQ. And by 1983, at least 15 laboratories throughout the world were working on various FWQ designs. In the early years, there were many types of geometry considered for the RFQ, but only a few types have survived. The two cavity geometries now used in almost all RFQs are the 4-vane and 4-rod structures. The 4-vane structure is the most popular because its operating frequency range (80 to -500 MHz) is suitable for light ions. Heavy ions require low frequencies (below 200 MHz). Because the 4-rod structure has smaller transverse dimensions than a 4-vane RFQ at the same frequency, the 4-rod RFQ is often preferred for these applications. This paper will describe how the RFQ accelerates and focuses the beam. The paper also discusses some of the important technical advances in designing and building RFQs.
Date:
January 1, 2002
Creator:
Young, L. M. (Lloyd M.)
Object Type:
Article
System:
The UNT Digital Library
148-Gd cross section measurements for accelerator target facilities
In a series of experiments at LANSCE's WNR facility, 148Gdp roduction was measured for 600- and 800-MeV protons on tungsten, tantalum, and gold. These experiments used 3 pm thin W, Ta, and Au foils and 10 pm thin A1 activation foils, Spallation yields were determined for many short-lived and long-lived spallation products with these foils using gamma and alpha spectroscopy.
Date:
January 1, 2002
Creator:
Corzine, R. K. (R. Karen); Pitcher, E. J. (Eric J.); Devlin, M. J. (Matthew J.) & Hertel, N. E. (Nolan E.)
Object Type:
Article
System:
The UNT Digital Library
2001 ''You Have the Power'' campaign [Federal Energy Management Program]. Final technical report
The Tasks of 2001 ''You Have the Power'' campaign by the Federal Energy Management Program (FEMP) are: Task 1--Interagency Planning Meetings; Task 2--Ear Day Event; Task 3--Earth Day and Energy Awareness Month Activities; Task 4--Regional Target; Task 5--Outreach Tools and Campaign Products; Task 6--Private Sector Participation; Task 7--''You Have the Power'' on the FEMP Web Site; and Task 8--Effective Communications.
Date:
January 1, 2002
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
2nd Annual Los Alamos Plutonium Metal Standard Exchange Workshop : "preliminary" results
The Rocky Flats Plutonium (Pu) Metal Sample Exchange program was conducted to insure the quality and intercomparability of measurements such as Pu assay, Pu isotopics, and impurity analyses. This program was discontinued in 1989 after more than 30 years. Los Alamos National Laboratory (LANL) has reestablished the Pu metal exchange program. During the first year, five DOE facilities, Argonne East, Argonne West, Livermore, Los Alamos, and New Brunswick Laboratory, Savannah River and the Atomic Weapons Establishment (AWE)' at Aldermaston are participating in the program. Plutonium metal samples are being prepared and distributed to the various sites primarily for destructive measurements for elemental concentration, isotopic abundance, and both metallic and nonmetallic impurity levels. The program is intended to provide independent verification of analytical measurement capability for each participating facility and to allow problems to be identified. Significants achievements in FY02 will be described. Results from category 1 elements and comparisons with Rocky Flats standards exchange metal historical data will also be presented. The roles and responsibilities of LANL and the external laboratories have been defined.
Date:
January 1, 2002
Creator:
Tandon, L. (Lav) & Slemmons, A. K. (Alice K.)
Object Type:
Article
System:
The UNT Digital Library
3D analysis of bainite morphologies and kinetics in alloy steels
Serial sectioning and 3D reconstruction of austenite decomposition products were undertaken in bay-forming ternary steels to better understand their true morphologies in the bay region of their TTT diagrams. Jagged growth interfaces are revealed in allotriomorphic bainite formed at the bay in Fe-0.24C-4M0, contrasting with the idealized geometries often assumed when formulating growth models. This also has implications for experimental thickening kinetics measurments. Examination of the so-called 'degenerate' ferrite formed below the bay in Fe-Ox-6.3 W reveals that it is not degenerate at all, but rather has a Widmanstatten rod morphology which gives the appearance of degeneracy due to the multiplicity of ways that they can intersect a randomly-oriented plane of polish. Furthermore, these rods are grouped in packets posessing a common elongation direction, highlighting the crystallographic nature of their formation. The impact of these findings on the understanding of austenite decomposition in bayforming steels will be discussed.
Date:
January 1, 2002
Creator:
Hackenberg, R. E. (Robert E.); Nordstrom, D. P. (Dale P.) & Shiflet, G. J. (Gary J.)
Object Type:
Article
System:
The UNT Digital Library
AC losses in prototype multistrand conductors for warm dielectric cable designs
We report on multiphase ac losses in four-layer prototype multi-strand conductors (PMCs) wound from EITS tape provided by American Superconductor Corporation. These conductors are prototypes warm dielectric cable designs, such as for the US Dept. of Energy's Superconductivity Partnership Initiative Project at Detroit Edison, We report on single phase 'two phaset'(no current in Ihe PMC but with an external ac magnetic field generated by the two normal Conductors arranged at the remaining corners of an equilateral triangle forming a three-phase configuration) ,and balanced three phase losses. Losses were also measured using a set of saddle coils to apply an ac magnetic field to the PMC. The losses were measured as a function of temperature, frequency, and current. We compare the losses for three PMCs, one (4LA) wound conventionally with equal pitch angles for all layers and the two others (4LB and 4LC) wound to achieve equal current distribution (UCD) among the layers, and thus lower singlephase losses in the operating region. In addition, 4LC was wound with a newer gcneration tape having a higher critical current. The PMC 4LC was found to have the lowest single, twophase, and three-phase losses.
Date:
January 1, 2002
Creator:
Willis, Jeffrey O.; Maley, Martin P.; Boening, Henirch J.; Coletta, Giacomo; Mele, Renata & Nassi, Marco
Object Type:
Article
System:
The UNT Digital Library
Accurate quantification of radioactive materials by x-ray fluorescence : gallium in plutonium metal /.
Two XRF specimen preparation methods were investigated for quantifying gallium in plutonium metal. Gallium in plutonium was chosen here as an example for demonstrating the efficacy of wavelength dispersive XRF for quantifying radioactive materials. The steps necessary to handle such materials safely will also be discussed. Quantification of plutonium samples by a well-established aqueous specimen preparation method resulted in relative precision and accuracy values of well less than 1%. As an alternative to the aqueous approach, a dried residue method was studied. Quantification of gallium in samples using this method resulted in relative precision and accuracy values an order of magnitude worse, but the method is faster, safer, and generates less waste than the aqueous process. The specimen preparation details and analysis results using each method will be presented here.
Date:
January 1, 2002
Creator:
Worley, C. G. (Christopher G.)
Object Type:
Article
System:
The UNT Digital Library
Active probing of cloud multiple scattering, optical depth, vertical thickness, and liquid water content using wide-angle imaging LIDAR.
At most optical wavelengths, laser light in a cloud lidar experiment is not absorbed but merely scattered out of the beam, eventually escaping the cloud via multiple scattering. There is much information available in this light scattered far from the input beam, information ignored by traditional 'on-beam' lidar. Monitoring these off-beam returns in a fully space- and time-resolved manner is the essence of our unique instrument, Wide Angle Imaging Lidar (WAIL). In effect, WAIL produces wide-field (60-degree full-angle) 'movies' of the scattering process and records the cloud's radiative Green functions. A direct data product of WAIL is the distribution of photon path lengths resulting from multiple scattering in the cloud. Following insights from diffusion theory, we can use the measured Green functions to infer the physical thickness and optical depth of the cloud layer, and, from there, estimate the volume-averaged liquid water content. WAIL is notable in that it is applicable to optically thick clouds, a regime in which traditional lidar is reduced to ceilometry. Here we present recent WAIL data oti various clouds and discuss the extension of WAIL to full diurnal monitoring by means of an ultra-narrow magneto-optic atomic line filter for daytime measurements.
Date:
January 1, 2002
Creator:
Love, Steven P.; Davis, A. B. (Anthony B.); Rohde, C. A. (Charles A.); Tellier, L. L. (Larry L.) & Ho, Cheng,
Object Type:
Article
System:
The UNT Digital Library
Active probing of cloud thickness and optical depth using wide-angle imaging LIDAR.
At most optical wavelengths, laser light in a cloud lidar experiment is not absorbed but merely scattered out of the beam, eventually escaping the cloud via multiple scattering. There is much information available in this light scattered far from the input beam, information ignored by traditional 'on-beam' lidar. Monitoring these off-beam returns in a fully space- and time-resolved manner is the essence of our unique instrument, Wide Angle Imaging Lidar (WAIL). In effect, WAIL produces wide-field (60{sup o} full-angle) 'movies' of the scattering process and records the cloud's radiative Green functions. A direct data product of WAIL is the distribution of photon path lengths resulting from multiple scattering in the cloud. Following insights from diffusion theory, we can use the measured Green functions to infer the physical thickness and optical depth of the cloud layer. WAIL is notable in that it is applicable to optically thick clouds, a regime in which traditional lidar is reduced to ceilometry. Section 2 covers the up-to-date evolution of the nighttime WAIL instrument at LANL. Section 3 reports our progress towards daytime capability for WAIL, an important extension to full diurnal cycle monitoring by means of an ultra-narrow magneto-optic atomic line filter. Section 4 describes …
Date:
January 1, 2002
Creator:
Love, Steven P.; Davis, A. B. (Anthony B.); Rohde, C. A. (Charles A.); Tellier, L. L. (Larry L.) & Ho, Cheng,
Object Type:
Article
System:
The UNT Digital Library
Active vibration damping in the presence of uncertainties.
Several control design techniques including PlD, LQG, and PPF are investigated For adive vibration damping of a cantilever beam with uncertain boundary conditions. Step disturbances were used to evaluate the performance of the designed controllers.
Date:
January 1, 2002
Creator:
Farrar, C. R. (Charles R.); Eisenhour, T. A. (Travis A.); Hatchett, S. (Sam) & Salazar, I. (Isaac)
Object Type:
Article
System:
The UNT Digital Library
Adaptive control in optical fibers
Adpative control in combination with ultrafast pulse shaping provides a compelling approach to defeat dispersion, distortion and harness nonlinear phenomena on the femtosecond timescale. Ultrafast pulses propagating in optical fibers generate a number of linear and nonlinear effects which affect the pulse during its travel. The main causes stem from the dependence of the index of refraction on frequency (given that short pulses have a large bandwidth) and from the so-called self-action effects which involve the dependence of the index of refraction on the pulse intensity (which is high given that the pulse energy is confined to a very short amount of time).
Date:
January 1, 2002
Creator:
Omenetto, F. G. (Fiorenzo G.)
Object Type:
Article
System:
The UNT Digital Library
Adaptive Restoration of Airborne Daedalus AADS1268 ATM Thermal Data
To incorporate the georegistration and restoration processes into airborne data processing in support of U.S. Department of Energy's nuclear emergency response task, we developed an adaptive restoration filter for airborne Daedalus AADS1268 ATM thermal data based on the Wiener filtering theory. Preliminary assessment shows that this filter enhances the detectability of small weak thermal anomalies in AADS1268 thermal images.
Date:
January 1, 2002
Creator:
Yuan, D.; Doak, E.; Guss, P. & Will, A.
Object Type:
Article
System:
The UNT Digital Library
Advanced characterization of twins using automated EBSD
This poster describes resuns obtained using an automated, crystallographically-based technique for twin identification. The technique is based on the automated EBSD. The key features of the analysis are identification of potential twin boundaries by their misorientation character, identification of the distinct boundary planes among the symmetrically equiwlent candidates. and validation of these boundaries through comparison with the boundary and twin plane traces in the sample cross section. Results on the application of this technique to deformation twins in zirconium are analyzed for the effect of twin type and amount and sense of uniaxial deformation. The accumulation of strain tends to increase the misorientation deviation at least to the degree of the trace deviation compared with recrystalllzation twins in nickel.
Date:
January 1, 2002
Creator:
Wright, S. I. (Stuart I.); Bingert, J. F. (John F.); Mason, T. A. (Thomas A.) & Larsen, Ryan J.
Object Type:
Article
System:
The UNT Digital Library
Advanced characterization of twins using automated electron backscatter diffraction
This paper describes results obtained using an automated, crystallographically-based technique for twin identification. The technique is based on the automated collection of spatially specific orientation measurements by electron backscatter diffraction (EBSD) in the scanning electron microscope (SEM). The key features of the analysis are identification of potential twin boundaries by their misorientation character, identification of the distinct boundary planes among the symmetrically equivalent candidates, and validation of these boundaries through comparison with the boundary and twin plane traces in the sample cross section. Results on the application of this technique to deformation twins in zirconium are analyzed for the effect of twin type and amount and sense of uniaxial deformation. The accumulation of strain tends to increase the misorientation deviation at least to the degree of the trace deviation compared with recrystallization twins in nickel. In addition to the results on characterizing the twin character, results on extending the twin analysis to automated identification of parent and daughter material for structures exhibiting twin deformation are reported as well.
Date:
January 1, 2002
Creator:
Wright, S. I. (Stuart I.); Bingert, J. F. (John F.); Mason, T. A. (Thomas A.) & Larson, R. J. (Ryan J.)
Object Type:
Article
System:
The UNT Digital Library
ADVANCED FLUE GAS CONDITIONING AS A RETROFIT UPGRADE TO ENHANCE PM COLLECTION FROM COAL-FIRED ELECTRIC UTILITY BOILERS
The U.S. Department of Energy and ADA Environmental Solutions are engaged in a project to develop commercial flue gas conditioning additives. The objective is to develop conditioning agents that can help improve particulate control performance of smaller or under-sized electrostatic precipitators on utility coal-fired boilers. The new chemicals will be used to control both the electrical resistivity and the adhesion or cohesivity of the fly ash. There is a need to provide cost-effective and safer alternatives to traditional flue gas conditioning with SO{sub 3} and ammonia. During this reporting quarter, installation of a flue gas conditioning system was completed at PacifiCorp Jim Bridger Power Plant. Performance testing was underway. Results will be detailed in the next quarterly and subsequent technical summary reports. Also in this quarter, discussions were initiated with a prospective long-term candidate plant. This plant fires a bituminous coal and has opacity performance issues related to fly ash re-entrainment. Ammonia conditioning has been proposed here, but there is interest in liquid additives as a safer alternative.
Date:
January 1, 2002
Creator:
Baldrey, Kenneth E.
Object Type:
Report
System:
The UNT Digital Library
ADVANCED GAS TURBINE SYSTEMS RESEARCH
None
Date:
January 1, 2002
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
ADVANCED GASIFICATION-BASED FUEL CONVERSION AND ELECTRIC ENERGY PRODUCTION SYSTEM
Boise Cascade Corporation and the Gas Technology Institute (GTI) are cooperating to develop, demonstrate and place in continuous operation an advanced biomass gasification-based power generation system suitable for near-term commercial deployment in the Forest Products Industry. The system will be used in conjunction with, rather than in place of, existing wood waste fired boilers and flue gas cleanup systems. The novel system will include three advanced technological components based on GTI's RENUGAS{reg_sign} and METHANE de-NOX{reg_sign} technologies, and a gas turbine-based power generation concept developed in DOE's High Performance Power System (HIPPS) program. The system has, as its objective, to avoid the major hurdles of high-pressure gasification, i.e., high-pressure fuel feeding and ash removal, and hot gas cleaning that are typical for conventional IGCC power generation. It aims to also minimize capital intensity and technology risks. The system is intended to meet the immediate needs of the forest products industry for highly efficient and environmentally friendly electricity and steam generation systems utilizing existing wood waste as fuel resources.
Date:
January 1, 2002
Creator:
Rabovitser, Joseph & Bryan, Bruce
Object Type:
Report
System:
The UNT Digital Library
Advanced Hydrotest Facility (AHF) large bore quadrupole focusing magnet system
The Advanced Hydrotest Facility (AHF) at Los Alamos will provide proton radiography of large-scale, dynamic events. The large bore (Case II) quadrupole focusing magnets are a subsystem in this facility, consisting of four complete imaging lines with a total of eight imaging plates and 52 quadrupole magnets. Each large bore quadrupole has an inner winding diameter of 660 mm and provides a gradient of 10.4 T/m with a 300 mm field of view. Each magnet is a two-layer saddle, contained by a three cm steel shell. The conductor is a Rutherford cable, soldered into a C-shaped copper channel. The magnets are cooled by the forced-flow of two-phase helium through coolant pipes. Since the winding must absorb bursts of 0.35 J/kg irradiation, both NbTi and Nb{sub 3}Sn designs are being considered.
Date:
January 1, 2002
Creator:
Jason, A. J. (Andrew J.); Walstrom, P. L. (Peter L.); Waynert, J. A. (Joseph A.); Schultz, J. (Joel); Camille, R. J.; Antaya, T. (Thomas) et al.
Object Type:
Article
System:
The UNT Digital Library
Advanced laser sensing receiver concepts based on FPA technology.
The ultimate performance of any remote sensor is ideally governed by the hardware signal-to-noise capability and allowed signal-averaging time. In real-world scenarios, this may not be realizable and the limiting factors may suggest the need for more advanced capabilities. Moving from passive to active remote sensors offers the advantage of control over the illumination source, the laser. Added capabilities may include polarization discrimination, instantaneous imaging, range resolution, simultaneous multi-spectral measurement, or coherent detection. However, most advanced detection technology has been engineered heavily towards the straightforward passive sensor requirements, measuring an integrated photon flux. The need for focal plane array technology designed specifically for laser sensing has been recognized for some time, but advances have only recently made the engineering possible. This paper will present a few concepts for laser sensing receiver architectures, the driving specifications behind those concepts, and test/modeling results of such designs.
Date:
January 1, 2002
Creator:
Jacobson, P. L. (Phillip L.); Petrin, R. R. (Roger R.); Jolin, J. L. (John L.); Foy, B. R. (Bernard R.); Lowrance, J. L. & Renda, G. (George)
Object Type:
Article
System:
The UNT Digital Library
Advanced Particle Control for Electric Discharge Light Systems
None
Date:
January 1, 2002
Creator:
Fornaciari, Neal R.
Object Type:
Report
System:
The UNT Digital Library
ADVANCED TECHNOLOGIES FOR STRIPPER GAS WELL ENHANCEMENT
As part of Task 1 in Advanced Technologies for Stripper Gas Well Enhancement, Schlumberger-Holditch Reservoir Technologies (H-RT) has joined with two Appalachian Basin producers, Great Lakes Energy Partners, LLC, and Belden & Blake Corporation to develop methodologies for identification and enhancement of stripper wells with economic upside potential. These industry partners have provided us with data for more than 700 wells in northwestern Pennsylvania. Phase 1 goals of this project are to develop and validate methodologies that can quickly and cost-effectively identify wells with enhancement potential. We have continued to enhance and streamline our software, and we are testing the final stages of our new Microsoft{trademark} Access/Excel based software. We are continuing to process the information and are identifying potential candidate wells that can be used in Phase 2 to validate the new methodologies. In addition, preparation of the final technical report is underway. During this quarter, we have presented our project and discussed the software to numerous Petroleum Technology Transfer Council (PTTC) workshops located in various regions of the United States.
Date:
January 1, 2002
Creator:
Boyer, Charles M., II & MacDonald, Ronald J.
Object Type:
Report
System:
The UNT Digital Library
The advancement of public awareness, concerning TRU waste characterization, using a virtual document.
Building public trust and confidence through openness is a goal of the DOE Carlsbad Field Office for the Waste Isolation Pilot Plant (WIPP). The objective of the virtual document described in this paper is to give the public an overview of the waste characterization steps, an understanding of how waste characterization instrumentation works, and the type and amount of data generated from a batch of drums. The document is intended to be published on a web page andlor distributed at public meetings on CDs. Users may gain as much information as they desire regarding the transuranic (TRU) waste characterization program, starting at the highest level requirements (drivers) and progressing to more and more detail regarding how the requirements are met. Included are links to: (1) drivers (which include laws, permits and DOE Orders) (2) various characterization steps required for transportation and disposal under WIPP's Hazardous Waste Facility Permit (3) physical/chemical basis for each characterization method (4) types of data produced (5) quality assurance process that accompanies each measurement
Date:
January 1, 2002
Creator:
West, Thomas B.; Burns, Timothy P.; Estill, Wesley G.; Riggs, M. J. (Matt J.); Taggart, Daniel P. & Punjak, Wayne A.
Object Type:
Article
System:
The UNT Digital Library
Advances in recording scattered light changes in crustacean nerve with electrical activation
We investigated optical changes associated with crustacean nerve stimulation using birefringent and large angle scattered light. Improved detection schemes disclosed high temporal structure of the optical signals and allowed further investigations of biophysical mechanisms responsible for such changes. Most studies of physiological activity in neuronal tissue use techniques that measure the electrical behavior or ionic permeability of the nerve, such as voltage or ion sensitive dyes injected into cells, or invasive electric recording apparatus. While these techniques provide high resolution, they are detrimental to tissue and do not easily lend themselves to clinical applications in humans. Electrical and chemical components of neural excitation evoke physical responses observed through changes in scattered and absorbed light. This method is suited for in-vivo applications. Intrinsic optical changes have shown themselves to be multifaceted in nature and point to several different physiological processes that occur with different time courses during neural excitation. Fast changes occur concomitantly with electrical events, and slow changes parallel metabolic events including changes in blood flow and oxygenation. Previous experiments with isolated crustacean nerves have been used to study the biophysical mechanisms of fast optical changes. However, they have been confounded by multiple superimposed action potentials which make it difficult …
Date:
January 1, 2002
Creator:
Carter, Kathleen M.; Rector, David M.; Martinez, Anne T.; Guerra, Francisco M. & George, John S.
Object Type:
Article
System:
The UNT Digital Library