Effective and efficient optics inspection approach using machine learning algorithms (open access)

Effective and efficient optics inspection approach using machine learning algorithms

The Final Optics Damage Inspection (FODI) system automatically acquires and utilizes the Optics Inspection (OI) system to analyze images of the final optics at the National Ignition Facility (NIF). During each inspection cycle up to 1000 images acquired by FODI are examined by OI to identify and track damage sites on the optics. The process of tracking growing damage sites on the surface of an optic can be made more effective by identifying and removing signals associated with debris or reflections. The manual process to filter these false sites is daunting and time consuming. In this paper we discuss the use of machine learning tools and data mining techniques to help with this task. We describe the process to prepare a data set that can be used for training and identifying hardware reflections in the image data. In order to collect training data, the images are first automatically acquired and analyzed with existing software and then relevant features such as spatial, physical and luminosity measures are extracted for each site. A subset of these sites is 'truthed' or manually assigned a class to create training data. A supervised classification algorithm is used to test if the features can predict the …
Date: November 2, 2010
Creator: Abdulla, G.; Kegelmeyer, L.; Liao, Z. & Carr, W.
Object Type: Article
System: The UNT Digital Library
Analysis of 14C and 13C in Teeth Provides Precise Birth Dating and Clues to Geographical Origin (open access)

Analysis of 14C and 13C in Teeth Provides Precise Birth Dating and Clues to Geographical Origin

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Date: August 2, 2010
Creator: Alkass, K.; Buchholz, B. A.; Druid, H. & Spalding, K. L.
Object Type: Article
System: The UNT Digital Library
Separation of High Order Harmonics with Fluoride Windows (open access)

Separation of High Order Harmonics with Fluoride Windows

The lower orders produced in high order harmonic generation can be effciently temporally separated into monochromatic pulses by propagation in a Fluoride window while still preserving their femtosecond pulse duration. We present calculations for MgF2, CaF2, and LiF windows for the third, fifth, and seventh harmonics of 800 nm. We demonstrate the use of this simple and inexpensive technique in a femtosecond pump/probe experiment using the fifth harmonic.
Date: August 2, 2010
Creator: Allison, Tom; van Tilborg, Jeroen; Wright, Travis; Hertlein, Marcus; Falcone, Roger & Belkacem, Ali
Object Type: Article
System: The UNT Digital Library
STM imaging of electronic waves on the surface of Bi2Te3: topologically protected surface states and hexagonal warping effects (open access)

STM imaging of electronic waves on the surface of Bi2Te3: topologically protected surface states and hexagonal warping effects

Scanning tunneling spectroscopy studies on high-quality Bi{sub 2}Te{sub 3} crystals exhibit perfect correspondence to ARPES data, hence enabling identification of different regimes measured in the local density of states (LDOS). Oscillations of LDOS near a step are analyzed. Within the main part of the surface band oscillations are strongly damped, supporting the hypothesis of topological protec- tion. At higher energies, as the surface band becomes concave, oscillations appear which disperse with a particular wave-vector that may result from an unconventional hexagonal warping term.
Date: June 2, 2010
Creator: Alpichshev, Zhanybek; /SIMES, Stanford /SLAC /Stanford U., Phys. Dept.; Analytis, J. G.; /SIMES, Stanford /SLAC /Stanford U., Phys. Dept.; Chu, J. H.; Fisher, I. R. et al.
Object Type: Article
System: The UNT Digital Library
Radiography Facility - Building 239 Independent Validation Review (open access)

Radiography Facility - Building 239 Independent Validation Review

The purpose of this task was to perform an Independent Validation Review to evaluate the successful implementation and effectiveness of Safety Basis controls, including new and revised controls, to support the implementation of a new DSA/TSR for B239. This task addresses Milestone 2 of FY10 PEP 7.6.6. As the first IVR ever conducted on a LLNL nuclear facility, it was designated a pilot project. The review follows the outline developed for Milestone 1 of the PEP, which is based on the DOE Draft Guide for Performance of Independent Verification Review of Safety Basis Controls. A formal Safety Basis procedure will be developed later, based on the lessons learned with this pilot project. Note, this review is termed a ''Validation'' in order to be consistent with the PEP definition and address issues historically raised about verification mechanisms at LLNL. Validation is intended to confirm that implementing mechanisms realistically establish the ability of TSR LCO, administrative control or safety management program to accomplish its intended safety function and that the controls are being implemented. This effort should not, however, be confused with a compliance assessment against all relevant DOE requirements and national standards. Nor is it used as a vehicle to question …
Date: February 2, 2010
Creator: Altenbach, T J; Beaulieu, R A; Watson, J F & Wong, H J
Object Type: Report
System: The UNT Digital Library
ARPES studies of the electronic structure of LaOFe(P,As) (open access)

ARPES studies of the electronic structure of LaOFe(P,As)

We report a comparison study of LaOFeP and LaOFeAs, two parent compounds of recently discovered iron-pnictide superconductors, using angle-resolved photoemission spectroscopy. Both systems exhibit some common features that are very different from well-studied cuprates. In addition, important differences have also been observed between these two ferrooxypnictides. For LaOFeP, quantitative agreement can be found between our photoemission data and the LDA band structure calculations, suggesting that a weak coupling approach based on an itinerant ground state may be more appropriate for understanding this new superconducting compound. In contrast, the agreement between LDA calculations and experiments in LaOFeAs is relatively poor, as highlighted by the unexpected Fermi surface topology around ({pi},{pi}). Further investigations are required for a comprehensive understanding of the electronic structure of LaOFeAs and related compounds.
Date: June 2, 2010
Creator: Analytis, J.G.
Object Type: Article
System: The UNT Digital Library
International Criminal Court Cases in Africa: Status and Policy Issues (open access)

International Criminal Court Cases in Africa: Status and Policy Issues

This report provides background on current International Criminal Court (ICC) cases and examines issues raised by the ICC's actions in Africa, including the potential deterrence of future abuses and the potential impact on African peace processes.
Date: April 2, 2010
Creator: Arieff, Alexis; Margesson, Rhoda & Browne, Marjorie Ann
Object Type: Report
System: The UNT Digital Library
Search for the B to K nu nu-bar Decay Using Semi-Leptonic Tags (open access)

Search for the B to K nu nu-bar Decay Using Semi-Leptonic Tags

We present an update of the search for the flavor-changing neutral current B{sup +} {yields} K{sup +}{nu}{bar {nu}} decay using 351 X 10{sup 6} B{bar B} pairs collected at the {Upsilon}(4S) resonance with the BABAR detector at the SLAC PEP-II B factory. Due to the presence of two neutrinos in the final state, we require the reconstruction of the companion B in the event through the decay channel B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}X. We find 38 candidates in the data with an expected background of 31{-+} 12. This allows us to set an upper limit on the branching fraction for B{sup +} {yields} K{sup +}{nu}{bar {nu}} of 4.5 X 10{sup -5} at 90% confidence level.
Date: June 2, 2010
Creator: Aubert, B.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X. et al.
Object Type: Article
System: The UNT Digital Library
A Design Report of the Baseline for PEP-X: an Ultra-Low Emittance Storage Ring (open access)

A Design Report of the Baseline for PEP-X: an Ultra-Low Emittance Storage Ring

Over the past year, we have worked out a baseline design for PEP-X, as an ultra-low emittance storage ring that could reside in the existing 2.2-km PEPII tunnel. The design features a hybrid lattice with double bend achromat (DBA) cells in two arcs and theoretical minimum emittance (TME) cells in the remaining four arcs. Damping wigglers are used to reduce the horizontal emittance to 86 pm-rad at zero current for a 4.5 GeV electron beam. At a design current of 1.5 A, the horizontal emittance increases, due to intrabeam scattering, to 164 pm-rad when the vertical emittance is maintained at a diffraction limited 8 pm-rad. The baseline design will produce photon beams achieving a brightness of 10{sup 22} (ph/s/mm{sup 2}/mrad{sup 2}/0.1% BW) at 10 keV in a 3.5-m conventional planar undulator. Our study shows that an optimized lattice has adequate dynamic aperture, while accommodating a conventional off-axis injection system. In this report, we present the results of study, including the lattice properties, nonlinear dynamics, intra-beam scattering and Touschek lifetime, RF system, and collective instabilities. Finally, we discuss the possibility of partial lasing at soft X-ray wavelengths using a long undulator in a straight section.
Date: June 2, 2010
Creator: Bane, Karl; Bertsche, Kirk; Cai, Yunhai; Chao, Alex; Corbett, Willian; Fox, John et al.
Object Type: Report
System: The UNT Digital Library
Government Access to Phone Calling Activity and Related Records: Legal Authorities (open access)

Government Access to Phone Calling Activity and Related Records: Legal Authorities

This report summarizes legal authorities regarding access by the government, for either foreign intelligence or law enforcement purposes, to information related to telephone calling patterns or practices. Where pertinent, it also discusses statutory prohibitions against accessing or disclosing such information, along with relevant exceptions to those prohibitions.
Date: February 2, 2010
Creator: Bazan, Elizabeth B.; Liu, Edward C. & Stevens, Gina
Object Type: Report
System: The UNT Digital Library
The Cost of Iraq, Afghanistan, and Other Global War on Terror Operations Since 9/11 (open access)

The Cost of Iraq, Afghanistan, and Other Global War on Terror Operations Since 9/11

In the ninth year of operations since the 9/11 attacks while troops are being withdrawn in Iraq and increased in Afghanistan, the cost of war continues to be a major issue including the total amount appropriated, the amount for each operation, average monthly spending rates, and the scope and duration of future costs. This report analyzes war funding for the Defense Department and tracks funding for USAID and VA Medical funding.
Date: September 2, 2010
Creator: Belasco, Amy
Object Type: Report
System: The UNT Digital Library
Next-to-Leading Order QCD Predictions for Z, gamma^* 3-Jet Distributions at the Tevatron (open access)

Next-to-Leading Order QCD Predictions for Z, gamma^* 3-Jet Distributions at the Tevatron

Using BlackHat in conjunction with SHERPA, we have computed next-to-leading order QCD predictions for a variety of distributions in Z, {gamma}{sup {asterisk}}+ 1, 2, 3-jet production at the Tevatron, where the Z boson or off-shell photon decays into an electron-positron pair. We find good agreement between the NLO results for jet {sub pT} distributions and measurements by CDF and D0. We also present jetproduction ratios, or probabilities of finding one additional jet. As a function of vector-boson {sub pT} , the ratios have distinctive features which we describe in terms of a simple model capturing leading logarithms and phase-space and parton-distribution-function suppression.
Date: June 2, 2010
Creator: Berger, C.F.; /MIT, LNS; Bern, Z.; /UCLA; Dixon, L.J.; /SLAC et al.
Object Type: Article
System: The UNT Digital Library
Bills and Resolutions: Examples of How Each Kind Is Used (open access)

Bills and Resolutions: Examples of How Each Kind Is Used

When Congress seeks to pass a law, it uses a bill or joint resolution, which must be passed by both houses in identical form, then presented to the President for his approval or disapproval. This report briefly describes this process.
Date: December 2, 2010
Creator: Beth, Richard S.
Object Type: Report
System: The UNT Digital Library
Alloy Design and Thermomechanical Processing of a Beta Titanium Alloy for a Heavy Vehicle Application (open access)

Alloy Design and Thermomechanical Processing of a Beta Titanium Alloy for a Heavy Vehicle Application

With the strength of steel, but at half the weight, titanium has the potential to offer significant benefits in the weight reduction of heavy vehicle components while possibly improving performance. However, the cost of conventional titanium fabrication is a major barrier in implementation. New reduction technologies are now available that have the potential to create a paradigm shift in the way the United States uses titanium, and the economics associated with fabrication of titanium components. This CRADA project evaluated the potential to develop a heavy vehicle component from titanium powders. The project included alloy design, development of manufacturing practices, and modeling the economics associated with the new component. New Beta alloys were designed for this project to provide the required mechanical specifications while utilizing the benefits of the new fabrication approach. Manufacturing procedures were developed specific to the heavy vehicle component. Ageing and thermal treatment optimization was performed to provide the desired microstructures. The CRADA partner established fabrication practices and targeted capital investment required for fabricating the component out of titanium. Though initial results were promising, the full project was not executed due to termination of the effort by the CRADA partner and economic trends observed in the heavy vehicle …
Date: July 2, 2010
Creator: Blue, Craig A. & Peter, William H.
Object Type: Report
System: The UNT Digital Library
VERTICAL PILLAR ARRAYS FOR PLASMON NANOCAVITIES (open access)

VERTICAL PILLAR ARRAYS FOR PLASMON NANOCAVITIES

We investigate tunable plasmon resonant cavity arrays in paired parallel nanowire waveguides. Resonances are observed when the waveguide length is an odd multiple of quarter plasmon wavelengths, consistent with boundary conditions of node and antinode at the ends. Two nanowire waveguides satisfy the dispersion relation of a planar metal-dielectric-metal waveguide of equivalent width equal to the square field average weighted gap. Confinement factors over 10{sup 3} are possible due to plasmon focusing in the inter-wire space.
Date: April 2, 2010
Creator: Bora, M.; Fasenfest, B. J.; Behymer, E. M.; Chang, A. S.; Hguyen, H. T.; Britten, J. A. et al.
Object Type: Article
System: The UNT Digital Library
Stardust and the Molecules of Life (Why are the Amino Acids Left-Handed?) (open access)

Stardust and the Molecules of Life (Why are the Amino Acids Left-Handed?)

A mechanism for creating and selecting amino acid chirality is identified, and subsequent chemical replication and galactic mixing that would populate the galaxy with the predominant species will be described. This involves: (1) the spin of the {sup 14}N in the amino acids, or in precursor molecules from which amino acids might be formed, coupling to the chirality of the molecules; (2) the neutrinos emitted from the supernova, together with magnetic field from the nascent neutron star or black hole from the supernova selectively destroying one orientation of the {sup 14}N, thereby selecting the chirality associated with the other {sup 14}N orientation; (3) amplification by chemical evolution, by which the molecules replicate on a relatively short timescale; and (4) galactic mixing on a longer timescale mixing the selected molecules throughout the galaxy.
Date: April 2, 2010
Creator: Boyd, Richard N.; Kajino, Toshitaka & Onaka, Takashi
Object Type: Article
System: The UNT Digital Library
Biomass: Comparison of Definitions in Legislation (open access)

Biomass: Comparison of Definitions in Legislation

This report investigates the characterization of Biomass in Legislation.
Date: February 2, 2010
Creator: Bracmort, Kelsi & Gorte, Ross W.
Object Type: Report
System: The UNT Digital Library
Electronic structure and spectroscopy of nucleic acid bases: Ionization energies, ionization-induced structural changes, and photoelectron spectra (open access)

Electronic structure and spectroscopy of nucleic acid bases: Ionization energies, ionization-induced structural changes, and photoelectron spectra

We report high-level ab initio calculations and single-photon ionization mass spectrometry study of ionization of adenine (A), thymine (T), cytosine (C) and guanine (G). For thymine and adenine, only the lowest-energy tautomers were considered, whereas for cytosine and guanine we characterized five lowest-energy tautomeric forms. The first adiabatic and several vertical ionization energies were computed using equation-of-motion coupled-cluster method for ionization potentials with single and double substitutions. Equilibrium structures of the cationic ground states were characterized by DFT with the {omega}B97X-D functional. The ionization-induced geometry changes of the bases are consistent with the shapes of the corresponding molecular orbitals. For the lowest-energy tautomers, the magnitude of the structural relaxation decreases in the following series G > C > A > T, the respective relaxation energies being 0.41, 0.32, 0.25 and 0.20 eV. The computed adiabatic ionization energies (8.13, 8.89, 8.51-8.67 and 7.75-7.87 eV for A,T,C and G, respectively) agree well with the onsets of the photoionization efficiency (PIE) curves (8.20 {+-} 0.05, 8.95 {+-} 0.05, 8.60 {+-} 0.05 and 7.75 {+-} 0.05 eV). Vibrational progressions for the S{sub 0}-D{sub 0} vibronic bands computed within double-harmonic approximation with Duschinsky rotations are compared with previously reported experimental photoelectron spectra.
Date: August 2, 2010
Creator: Bravaya, Ksenia B.; Kostko, Oleg; Dolgikh, Stanislav; Landau, Arie; Ahmed, Musahid & Krylov, Anna I.
Object Type: Article
System: The UNT Digital Library
Fishery, Aquaculture, and Marine Mammal Issues in the 111th Congress (open access)

Fishery, Aquaculture, and Marine Mammal Issues in the 111th Congress

This report gives an overview of Fishery, Aquaculture, and Marine Mammal Issues in the 111th Congress
Date: September 2, 2010
Creator: Buck, Eugene H.
Object Type: Report
System: The UNT Digital Library
229Th the Bridge Between Nuclear and Atomic Interactions (open access)

229Th the Bridge Between Nuclear and Atomic Interactions

The precise measurement of time has been a goal of physicists for centuries. With every new increase in our ability to measure time we have discovered new phenomena. The most advanced clocks available to us currently are atomic clocks that use electronic transitions to track the passage of time. In this proposal, I put forward the framework for the first nuclear clock estimated to be 1000 to 10000 times more precise than the current atomic clocks. This research will explore in detail the atomic nuclear interactions and help perfect and refine current atomic-nuclear interaction models. The realization of a {sup 229}Th nuclear clock will allow tests of cosmology by measuring the change of the fine structure constant as a function of time. The results of these experiments could dramatically alter our view of the universe, its past and future evolution. Precision clocks - with fundamental physics applications - require a long-lived quantum transition (two-level system) that is immune to external perturbations. Nuclear transitions would be better suited than atomic transitions for these applications except that nuclear transitions are typically much higher in energy and therefore cannot be accessed with table-top lasers. There is, however, one promising nuclear transition: the doublet …
Date: December 2, 2010
Creator: Burke, J T; Casperson, R J; Swanberg, E L & Thomas, D
Object Type: Report
System: The UNT Digital Library
Report on 238Pu(n,x) surrogate cross section measurement (open access)

Report on 238Pu(n,x) surrogate cross section measurement

The goal of this year's effort is to measure the {sup 238}Pu(n,f) and {sup 238}Pu(n,2n) cross section from 100 keV to 20 MeV. We designed a surrogate experiment that used the reaction {sup 239}Pu(a,a{prime}x) as a surrogate for {sup 238}Pu(n,x). The experiment was conducted using the STARS/LIBERACE experimental facility located at the 88 Inch Cyclotron at Lawrence Berkeley National Laboratory in January 2010. A description of the experiment and status of the data analysis is given. In order to obtain a reliable {sup 238}Pu(n,x) cross section we designed the experiment using the surrogate ratio technique. This technique allows one to measure a desired, unknown, cross section relative to a known cross section. In the present example, the {sup 238}Pu(n,x) cross section of interest is determined relative to the known {sup 235}U(n,x) cross section. To increase confidence in the results, and to reduce overall uncertainties, we are also determining the {sup 238}Pu(n,x) cross section relative to the known {sup 234}U(n,x) cross section. The compound nuclei of interest for this experiment were produced using inelastic alpha scattering. For example, {sup 236}U(a,a{prime}x) served as a surrogate for {sup 235}U(n,x); analogous reactions were considered for the other cross sections. Surrogate experiments determine the probabilities …
Date: April 2, 2010
Creator: Burke, J. T.; Ressler, J. J.; Henderson, R. A.; Scielzo, N. D.; Escher, J. E.; Thompson, I. J. et al.
Object Type: Report
System: The UNT Digital Library
Deuterium Retention in NSTX with Lithium Conditioning (open access)

Deuterium Retention in NSTX with Lithium Conditioning

High (≈ 90%) deuterium retention was observed in NSTX gas balance measurements both withand without lithiumization of the carbon plasma facing components. The gas retained in ohmic discharges was measured by comparing the vessel pressure rise after a discharge to that of a gasonly pulse with the pumping valves closed. For neutral beam heated discharges the gas input and gas pumped by the NB cryopanels were tracked. The discharges were followed by outgassing of deuterium that reduced the retention. The relationship between retention and surface chemistry was explored with a new plasma-material interface probe connected to an in-vacuo surface science station that exposed four material samples to the plasma. XPS and TDS analysis showed that the binding of D atoms is fundamentally changed by lithium - in particular atoms are weakly bonded in regions near lithium atoms bound to either oxygen or the carbon matrix.
Date: June 2, 2010
Creator: C.H. Skinner, J.P. Allain, W. Blanchard, H.W. Kugel, R. Maingi, L. Roquemore, V. Soukhanovskii, C.N. Taylor
Object Type: Article
System: The UNT Digital Library
Model-Based Detection of Radioactive Contraband for Harbor Defense Incorporating Compton Scattering Physics (open access)

Model-Based Detection of Radioactive Contraband for Harbor Defense Incorporating Compton Scattering Physics

The detection of radioactive contraband is a critical problem is maintaining national security for any country. Photon emissions from threat materials challenge both detection and measurement technologies especially when concealed by various types of shielding complicating the transport physics significantly. This problem becomes especially important when ships are intercepted by U.S. Coast Guard harbor patrols searching for contraband. The development of a sequential model-based processor that captures both the underlying transport physics of gamma-ray emissions including Compton scattering and the measurement of photon energies offers a physics-based approach to attack this challenging problem. The inclusion of a basic radionuclide representation of absorbed/scattered photons at a given energy along with interarrival times is used to extract the physics information available from the noisy measurements portable radiation detection systems used to interdict contraband. It is shown that this physics representation can incorporated scattering physics leading to an 'extended' model-based structure that can be used to develop an effective sequential detection technique. The resulting model-based processor is shown to perform quite well based on data obtained from a controlled experiment.
Date: March 2, 2010
Creator: Candy, J V; Chambers, D H; Breitfeller, E F; Guidry, B L; Verbeke, J M; Axelrod, M A et al.
Object Type: Article
System: The UNT Digital Library
The Economics of the Federal Budget Deficit (open access)

The Economics of the Federal Budget Deficit

This report examines the economics the budget deficit. Topics include recent budgetary history, the differences made by deficits and surpluses, and fiscal policy.
Date: February 2, 2010
Creator: Cashell, Brian W.
Object Type: Report
System: The UNT Digital Library