Geometrical theory of nonlinear phase distortion of intense laser beams (open access)

Geometrical theory of nonlinear phase distortion of intense laser beams

Phase distortion arising from whole beam self-focusing of intense laser pulses with arbitrary spatial profiles is treated in the limit of geometrical optics. The constant shape approximation is used to obtain the phase and angular distribution of the geometrical rays in the near field. Conditions for the validity of this approximation are discussed. Geometrical focusing of the aberrated beam is treated for the special case of a beam with axial symmetry. Equations are derived that show both the shift of the focus and the distortion of the intensity distribution that are caused by the nonlinear index of refraction of the optical medium. An illustrative example treats the case of beam distortion in a Nd:Glass amplifier.
Date: May 7, 1975
Creator: Glaze, J. A.; Hunt, J. T. & Speck, D. R.
Object Type: Report
System: The UNT Digital Library
Surveillance of Site A and Plot M, Report for 2008. (open access)

Surveillance of Site A and Plot M, Report for 2008.

The results of the environmental surveillance program conducted at Site A/Plot M in the Palos Forest Preserve area for Calendar Year 2008 are presented. Based on the results of the 1976-1978 radiological characterization of the site, a determination was made that a surveillance program be established. The characterization study determined that very low levels of hydrogen-3 (as tritiated water) had migrated from the burial ground and were present in two nearby hand pumped picnic wells. The current surveillance program began in 1980 and consists of sample collection and analysis of surface and subsurface water. The results of the analyses are used to (1) monitor the migration pathway of hydrogen-3 contaminated water from the burial ground (Plot M) to the hand-pumped picnic wells, (2) establish if other buried radionuclides have migrated, and (3) monitor for the presence of radioactive materials in the environment of the area. Hydrogen-3 in the Red Gate Woods picnic wells was still detected this year, but the average and maximum concentrations were significantly less than found earlier. Hydrogen-3 continues to be detected in a number of wells, boreholes, dolomite holes, and a surface stream. Analyses since 1984 have indicated the presence of low levels of strontium-90 in …
Date: May 7, 2009
Creator: Golchert, N. W.
Object Type: Report
System: The UNT Digital Library
Surveillance of Site A and Plot M - Report for 2006. (open access)

Surveillance of Site A and Plot M - Report for 2006.

The results of the environmental surveillance program conducted at Site A/Plot M in the Palos Forest Preserve area for Calendar Year 2006 are presented. Based on the results of the 1976-1978 radiological characterization of the site, a determination was made that a surveillance program be established. The characterization study determined that very low levels of hydrogen-3 (as tritiated water) had migrated from the burial ground and were present in two nearby hand-pumped picnic wells. The current surveillance program began in 1980 and consists of sample collection and analysis of surface and subsurface water. The results of the analyses are used to (1) monitor the migration pathway of water from the burial ground (PlotM) to the hand pumped picnic wells, (2) establish if buried radionuclides other than hydrogen-3 have migrated, and (3) monitor the presence of radioactive and chemically hazardous materials in the environment of the area. Hydrogen-3 in the Red GateWoods picnic wells was still detected this year, but the average and maximum concentrations were significantly less than found earlier. Hydrogen-3 continues to be detected in a number of wells, boreholes, dolomite holes, and a surface stream. Analyses since 1984 have indicated the presence of low levels of strontium-90 in …
Date: May 7, 2007
Creator: Golchert, N. W. & Oversight, ESH /QA
Object Type: Report
System: The UNT Digital Library
Novel transport-vehicle design for moving optic modules in the National Ignition Facility (open access)

Novel transport-vehicle design for moving optic modules in the National Ignition Facility

The National Ignition Facility, currently under design and construction at Lawrence Livermore National Laboratory, will be the world`s largest laser when complete. The NIF will use about 8,000 large optics of 26 different types to focus up to 192 laser beams on a dime-size target. Given the constraints of the NIF operating environment, the tasks associated with optics transport and handling require a novel, versatile transport system. The system will consist of a computer system containing guidance, traffic management and order entry functions, and four or more automated laser-guided vehicles. This transport system will transport optics enclosures that are essentially portable clean rooms and will lift, align, and position them as needed to contact and engage mating points on the laser support structure.
Date: May 7, 1998
Creator: Grasz, E. & Tiszauer, D.
Object Type: Article
System: The UNT Digital Library
Base case conditions for assistance to Hanford program, K-effluent system analysis, ATH-IP-5-64 (open access)

Base case conditions for assistance to Hanford program, K-effluent system analysis, ATH-IP-5-64

None
Date: May 7, 1964
Creator: Graves, S. M.
Object Type: Report
System: The UNT Digital Library
Observation of Single Collisionally Cooled Trapped Ions in a Buffer Gas (open access)

Observation of Single Collisionally Cooled Trapped Ions in a Buffer Gas

None
Date: May 7, 2007
Creator: Green, M.; Wodin, J.; DeVoe, R.; Fierlinger, P.; Flatt, B.; Gratta, G. et al.
Object Type: Article
System: The UNT Digital Library
The Mice Focusing Solenoids and their Cooling System (open access)

The Mice Focusing Solenoids and their Cooling System

This report describes the focusing solenoid for the proposed Muon Ionization Cooling Experiment (MICE) [1]. The focusing solenoid consists of a pair of superconducting solenoids that are on a common bobbin. The two coils, which have separate leads, may be operated in the same polarity or at opposite polarity. This report discusses the superconducting magnet design and the cryostat design for the MICE focusing module. Also discussed is how this superconducting magnet can be integrated with a pair of small 4.2 K coolers.
Date: May 7, 2004
Creator: Green, M.A.; Barr, G.; Lau, W.; Senanayake, R.S. & Yang, S.Q.
Object Type: Article
System: The UNT Digital Library
Lack of Bystander Effects From High LET Radiation For Early Cytogenetic Endpoints. (open access)

Lack of Bystander Effects From High LET Radiation For Early Cytogenetic Endpoints.

The aim of this work was to study radiation-induced bystander effects for early cytogenetic end points in various cell lines using the medium transfer technique after exposure to high- and low-LET radiation. Cells were exposed to 20 MeV/ nucleon nitrogen ions, 968 MeV/nucleon iron ions, or 575 MeV/nucleon iron ions followed by transfer of the conditioned medium from the irradiated cells to unirradiated test cells. The effects studied included DNA double-strand break induction, {gamma}-H2AX focus formation, induction of chromatid breaks in prematurely condensed chromosomes, and micronucleus formation using DNA repair-proficient and -deficient hamster and human cell lines (xrs6, V79, SW48, MO59K and MO59J). Cell survival was also measured in SW48 bystander cells using X rays. Although it was occasionally possible to detect an increase in chromatid break levels using nitrogen ions and to see a higher number of {gamma}-H2AX foci using nitrogen and iron ions in xrs6 bystander cells in single experiments, the results were not reproducible. After we pooled all the data, we could not verify a significant bystander effect for any of these end points. Also, we did not detect a significant bystander effect for DSB induction or micronucleus formation in these cell lines or for clonogenic survival …
Date: May 7, 2008
Creator: Groesser, Torsten; Cooper, Brian & Rydberg, Bjorn
Object Type: Article
System: The UNT Digital Library
TreeQ-VISTA: An Interactive Tree Visualization Tool with Functional Annotation Query Capabilities (open access)

TreeQ-VISTA: An Interactive Tree Visualization Tool with Functional Annotation Query Capabilities

Summary: We describe a general multiplatform exploratorytool called TreeQ-Vista, designed for presenting functional annotationsin a phylogenetic context. Traits, such as phenotypic and genomicproperties, are interactively queried from a relational database with auser-friendly interface which provides a set of tools for users with orwithout SQL knowledge. The query results are projected onto aphylogenetic tree and can be displayed in multiple color groups. A richset of browsing, grouping and query tools are provided to facilitatetrait exploration, comparison and analysis.Availability: The program,detailed tutorial and examples are available online athttp://genome-test.lbl.gov/vista/TreeQVista.
Date: May 7, 2007
Creator: Gu, Shengyin; Anderson, Iain; Kunin, Victor; Cipriano, Michael; Minovitsky, Simon; Weber, Gunther et al.
Object Type: Article
System: The UNT Digital Library
Improving the bulk data transfer experience (open access)

Improving the bulk data transfer experience

Scientific computations and collaborations increasingly rely on the network to provide high-speed data transfer, dissemination of results, access to instruments, support for computational steering, etc. The Energy Sciences Network is establishing a science data network to provide user driven bandwidth allocation. In a shared network environment, some reservations may not be granted due to the lack of available bandwidth on any single path. In many cases, the available bandwidth across multiple paths would be sufficient to grant the reservation. In this paper we investigate how to utilize the available bandwidth across multiple paths in the case of bulk data transfer.
Date: May 7, 2008
Creator: Guok, Chin; Guok, Chin; Lee, Jason R. & Berket, Karlo
Object Type: Article
System: The UNT Digital Library
VALIDATION OF COMPUTER MODELS FOR RADIOACTIVE MATERIAL SHIPPING PACKAGES (open access)

VALIDATION OF COMPUTER MODELS FOR RADIOACTIVE MATERIAL SHIPPING PACKAGES

Computer models are abstractions of physical reality and are routinely used for solving practical engineering problems. These models are prepared using large complex computer codes that are widely used in the industry. Patran/Thermal is such a finite element computer code that is used for solving complex heat transfer problems in the industry. Finite element models of complex problems involve making assumptions and simplifications that depend upon the complexity of the problem and upon the judgment of the analysts. The assumptions involve mesh size, solution methods, convergence criteria, material properties, boundary conditions, etc. that could vary from analyst to analyst. All of these assumptions are, in fact, candidates for a purposeful and intended effort to systematically vary each in connection with the others to determine there relative importance or expected overall effect on the modeled outcome. These kinds of models derive from the methods of statistical science and are based on the principles of experimental designs. These, as all computer models, must be validated to make sure that the output from such an abstraction represents reality [1,2]. A new nuclear material packaging design, called 9977, which is undergoing a certification design review, is used to assess the capability of the Patran/Thermal …
Date: May 7, 2007
Creator: Gupta, N; Gene Shine, G & Cary Tuckfield, C
Object Type: Article
System: The UNT Digital Library
Advanced Algorithms and Automation Tools for Discrete Ordinates Methods in Parallel Environments (open access)

Advanced Algorithms and Automation Tools for Discrete Ordinates Methods in Parallel Environments

This final report discusses major accomplishments of a 3-year project under the DOE's NEER Program. The project has developed innovative and automated algorithms, codes, and tools for solving the discrete ordinates particle transport method efficiently in parallel environments. Using a number of benchmark and real-life problems, the performance and accuracy of the new algorithms have been measured and analyzed.
Date: May 7, 2003
Creator: Haghighat, Alireza
Object Type: Report
System: The UNT Digital Library
D to A Line Tuning (open access)

D to A Line Tuning

Although in the past the D to A line was well tuned, through the course of years of operations it has not kept up with changes in the Debuncher and Accumulator. The beam is now steered well off center in SEM's 806 and 807, and is possibly scraping in TQ5. In addition, there is some evidence that the beta functions are not matched, causing emmitance blowup of the beam. As the cycle time of the main ring has decreased these limitations have become a significant limitation to the stacking rate.
Date: May 7, 1991
Creator: Halling, Mike
Object Type: Report
System: The UNT Digital Library
INCREASING HEAVY OIL RESERVES IN THE WILMINGTON OIL FIELD THROUGH ADVANCED RESERVOIR CHARACTERIZATION AND THERMAL PRODUCTION TECHNOLOGIES (open access)

INCREASING HEAVY OIL RESERVES IN THE WILMINGTON OIL FIELD THROUGH ADVANCED RESERVOIR CHARACTERIZATION AND THERMAL PRODUCTION TECHNOLOGIES

The project involves using advanced reservoir characterization and thermal production technologies to improve thermal recovery techniques and lower operating and capital costs in a slope and basin clastic (SBC) reservoir in the Wilmington field, Los Angeles Co., CA. Through September 2000, project work has been completed on the following activities: data preparation; basic reservoir engineering; developing a deterministic three dimensional (3-D) geologic model, a 3-D deterministic reservoir simulation model and a rock-log model; well drilling and completions; and surface facilities on the Fault Block II-A Tar Zone (Tar II-A). Work is continuing on improving core analysis techniques, final reservoir tracer work, operational work and research studies to prevent thermal-related formation compaction in the Tar II-A steamflood area, and operational work on the Tar V steamflood pilot and Tar II-A post steamflood projects. Work was discontinued on the stochastic geologic model and developing a 3-D stochastic thermal reservoir simulation model of the Tar II-A Zone so the project team could use the 3-D deterministic reservoir simulation model to provide alternatives for the Tar II-A post steamflood operations and shale compaction studies. The project team spent the fourth quarter 2000 performing well work and reservoir surveillance on the Tar II-A post-steamflood project …
Date: May 7, 2001
Creator: Hara, Scott
Object Type: Report
System: The UNT Digital Library
Design and analysis of isentropic compression experiments (open access)

Design and analysis of isentropic compression experiments

The use of magnetic flux compression to isentropically compress matter is summarized. Details of the process used to extract boundary data from the flash radiographs and the design criteria for the containment of very compressible material are discussed. Finally, suggestions for improvement of the next generation of experiments are made.
Date: May 7, 1979
Creator: Hawke, R. S.
Object Type: Article
System: The UNT Digital Library
2005 Tour de Sol: The Sustainable Energy and Transportation Festival and Competition (open access)

2005 Tour de Sol: The Sustainable Energy and Transportation Festival and Competition

This report gives a summary of the 2005Tour de Sol: The Sustainable Energy and Transportation Festival and Competition. It lists our objectives, what we did, and an analysis of how we met our objectives. An 80-page report with a list of verified print, radio and TV media coverage, and copies of selected news clips and web media coverage is available at the NESEA office for review.
Date: May 7, 2005
Creator: Hazard, Nancy
Object Type: Report
System: The UNT Digital Library
Web document clustering using hyperlink structures (open access)

Web document clustering using hyperlink structures

With the exponential growth of information on the World Wide Web there is great demand for developing efficient and effective methods for organizing and retrieving the information available. Document clustering plays an important role in information retrieval and taxonomy management for the World Wide Web and remains an interesting and challenging problem in the field of web computing. In this paper we consider document clustering methods exploring textual information hyperlink structure and co-citation relations. In particular we apply the normalized cut clustering method developed in computer vision to the task of hyperdocument clustering. We also explore some theoretical connections of the normalized-cut method to K-means method. We then experiment with normalized-cut method in the context of clustering query result sets for web search engines.
Date: May 7, 2001
Creator: He, Xiaofeng; Zha, Hongyuan; Ding, Chris H.Q & Simon, Horst D.
Object Type: Report
System: The UNT Digital Library
Determination of performance criteria for high-level solidified nuclear waste (open access)

Determination of performance criteria for high-level solidified nuclear waste

To minimize radiological risk from the operation of a waste management system, performance limits on volatilization, particulate dispersion, and dissolution characteristics of solidified high level waste must be specified. The results show clearly that the pre-emplacement environs are more limiting in establishing the waste form performance criteria than the post-emplacement environs. Absolute values of expected risk are very sensitive to modeling assumptions. The transportation and interim storage operations appear to be most limiting in determining the performance characteristics required. The expected values of risk do not rely upon the repositories remaining intact over the potentially hazardous lifetime of the waste.
Date: May 7, 1979
Creator: Heckman, R.A. & Holdsworth, T.
Object Type: Report
System: The UNT Digital Library
Advanced lubrication systems and materials. Final report (open access)

Advanced lubrication systems and materials. Final report

This report described the work conducted at the National Institute of Standards and Technology under an interagency agreement signed in September 1992 between DOE and NIST for 5 years. The interagency agreement envisions continual funding from DOE to support the development of fuel efficient, low emission engine technologies in terms of lubrication, friction, and wear control encountered in the development of advanced transportation technologies. However, in 1994, the DOE office of transportation technologies was reorganized and the tribology program was dissolved. The work at NIST therefore continued at a low level without further funding from DOE. The work continued to support transportation technologies in the development of fuel efficient, low emission engine development. Under this program, significant progress has been made in advancing the state of the art of lubrication technology for advanced engine research and development. Some of the highlights are: (1) developed an advanced high temperature liquid lubricant capable of sustaining high temperatures in a prototype heat engine; (2) developed a novel liquid lubricant which potentially could lower the emission of heavy duty diesel engines; (3) developed lubricant chemistries for ceramics used in the heat engines; (4) developed application maps for ceramic lubricant chemistry combinations for design purpose; …
Date: May 7, 1998
Creator: Hsu, S.
Object Type: Report
System: The UNT Digital Library
Determination of beryllium in urine, hair, fingernail, and fecal samples by flameless atomic absorption spectrometry (open access)

Determination of beryllium in urine, hair, fingernail, and fecal samples by flameless atomic absorption spectrometry

Methods for determining trace amounts of beryllium in urine, hair, fingernail, and fecal samples are described. These methods involve use of a Perkin-Elmer Model 503 spectrophotometer equipped with an HGA-2100 graphite furnace. Lanthanum was used as a masking and enhancing agent, and recoveries were determined by direct comparison with aqueous standards. The hair and fingernail samples were degraded readily in a nitric acid-perchloric acid mixture, and the feces were digested rapidly using a ferrous ion, hydrogen peroxide method. The urine samples were run by two methods: (1) direct and (2) coprecipitation. Nanogram-per-gram levels of beryllium were recovered from all tissues and fluids. All recoveries varied from 90 to 110 percent with relative standard deviations of less than 13 percent.
Date: May 7, 1976
Creator: Hurlbut, J. A.
Object Type: Report
System: The UNT Digital Library
Flameless atomic absorption determination of beryllium in the presence of various anions and cations (open access)

Flameless atomic absorption determination of beryllium in the presence of various anions and cations

A method for determining trace amounts of beryllium in the presence of various anions and cations is described. The method involves use of a Perkin-Elmer Model 503 spectrophotometer equipped with an HGA-2100 graphite furnace. The absorption signal from 20 ng/ml of beryllium varies significantly from acid to acid, and both 5 percent (V/V) nitric acid and 5 percent (V/V) sulfuric acid were studied as possible analysis solvents. Absorption signal enhancement and suppression caused by the presence of other chemicals appears similar in either solvent. Concentrations of more than 0.1M hydrochloric and hydrofluoric acid suppress the signal in both solvents. Group II cations, lanthanum, cerium, chromium, molybdenum, tungsten, manganese, aluminum, and silicon, when present in concentrations of 100 ..mu..g/ml, enhance the beryllium signal. The addition of 100 ..mu..g/ml of lanthanum increases the signal over two fold and masks the signal enhancement caused by the other listed elements; however, hydrochloric and hydrofluoric acids still interfere. The recovery of 20 ng/ml of beryllium in the presence of 100 ..mu..g/ml of lanthanum and in the presence of 100 ..mu..g/ml each of thirty elements tested is 20 ..mu..g/ml with a relative standard deviation of 4 percent and a range of 19 to 22 ng/ml. The …
Date: May 7, 1976
Creator: Hurlbut, J. A. & Bokowski, D. L.
Object Type: Report
System: The UNT Digital Library
Out-of-Core Compression and Decompression of Large n-Dimensional Scalar Fields (open access)

Out-of-Core Compression and Decompression of Large n-Dimensional Scalar Fields

We present a simple method for compressing very large and regularly sampled scalar fields. Our method is particularly attractive when the entire data set does not fit in memory and when the sampling rate is high relative to the feature size of the scalar field in all dimensions. Although we report results for R{sup 3} and R{sup 4} data sets, the proposed approach may be applied to higher dimensions. The method is based on the new Lorenzo predictor, introduced here, which estimates the value of the scalar field at each sample from the values at processed neighbors. The predicted values are exact when the n-dimensional scalar field is an implicit polynomial of degree n-1. Surprisingly, when the residuals (differences between the actual and predicted values) are encoded using arithmetic coding, the proposed method often outperforms wavelet compression in an L{infinity} sense. The proposed approach may be used both for lossy and lossless compression and is well suited for out-of-core compression and decompression, because a trivial implementation, which sweeps through the data set reading it once, requires maintaining only a small buffer in core memory, whose size barely exceeds a single n-1 dimensional slice of the data.
Date: May 7, 2003
Creator: Ibarria, L.; Lindstrom, P.; Rossignac, J. & Szymczak, A.
Object Type: Article
System: The UNT Digital Library
Refining of fossil resin flotation concentrates from Western coal. Final fifth quarterly report, January 1, 1994--March 31, 1994 (open access)

Refining of fossil resin flotation concentrates from Western coal. Final fifth quarterly report, January 1, 1994--March 31, 1994

Fossil resins occurring in the Wasatch Plateau coal field are composed mainly of aliphatic components, partially aromatized multi-cyclic terpenoids and a few oxygen functional groups (such as {minus}OH and {minus}COOH). The solvent extracted resins show the presence of a relatively large number of methyl groups when compared to the methylene groups, and this indicates the presence of extensive tertiary carbon and/or highly branching chains. In contrast coal consists primarily of aromatic ring structures, various oxygen functional groups ({minus}OH, >C=O, {minus}C{minus}O) and few aliphatic chains. The color difference observed among the four resin types is explained by the presence of chromophores (aromatized polyterpenoid) and also by the presence of finely dispersed coal particle inclusions in the resin matrix. The hexane soluble resin fraction has few aromatic compounds when compared to the hexane insoluble but toluene soluble resin fraction.
Date: May 7, 1994
Creator: Jensen, G. F. & Miller, J. D.
Object Type: Report
System: The UNT Digital Library
Periscope Pop-in Beam Monitor. (open access)

Periscope Pop-in Beam Monitor.

We have built monitors for use as beam diagnostics in the narrow gap of an undulator for an FEL experiment. They utilize an intercepting screen of doped YAG scintillating crystal to make light that is imaged through a periscope by conventional video equipment. The absolute position can be ascertained by comparing the electron beam position with the position of a He:Ne laser that is observed by this pop-in monitor. The optical properties of the periscope and the mechanical arrangement of the system mean that beam can be spatially determined to the resolution of the camera, in this case approximately 10 micrometers. Our experience with these monitors suggests improvements for successor designs, which we also describe.
Date: May 7, 1998
Creator: Johnson, E. D.
Object Type: Article
System: The UNT Digital Library