Matching Shapes Using Local Descriptors (open access)

Matching Shapes Using Local Descriptors

We present a method for comparing shapes of grayscale images in noisy circumstances. By establishing correspondences in a new image with a shape model, we can estimate a transformation between the new region and the model. Using a cost function for deviations from the model, we can rank resulting shape matches. We compare two separate distinct region detectors: Scale Saliency and difference of gaussians. We show that this method is successful in comparing images of fluid mixing under anisotropic geometric distortions and additive gaussian noise. Scale Saliency outperforms the difference of Gaussians in this context.
Date: August 13, 2004
Creator: White, R; Newsam, S & Kamath, C
Object Type: Report
System: The UNT Digital Library
Optimization and Harmonization of Radiation Monitoring at Nuclear Facilities Through ISO 14001 Compliance (open access)

Optimization and Harmonization of Radiation Monitoring at Nuclear Facilities Through ISO 14001 Compliance

None
Date: August 13, 2004
Creator: Rauhut, K A
Object Type: Article
System: The UNT Digital Library
Proposal for Reduction of Transverse Emittance of Bnl 200 Mev Linac. (open access)

Proposal for Reduction of Transverse Emittance of Bnl 200 Mev Linac.

BNL has a plan to upgrade the AGS proton beam from the current 0.14 MW to higher than 1.0 MW and beyond for a neutrino facility which consists of two major subsystems. First is a 1.45 GeV superconducting linac (SCL) to replace the Booster as injector for the AGS. Second is the performance upgrade for the AGS itself for the higher intensity and repetition rate. For high intensity proton accelerators, such as the upgraded AGS, there are very stringent limitations on uncontrolled beam losses. A direct effect of increased linac beam emittance is the halohail generation in the circulating beam. Studies show the estimated halohail generation in the beam for the present normalized RMS emittance of the linac beam is unacceptable. To reduce the transverse emittance of the 200 MeV linac, the existing radio frequency quadrupole linac (RFQ) has to be relocated closer to drift tube linac (DTL) tank 1 to meet the emittance requirement for AGS injection with low loss. This paper will present the various options of matching between RFQ and DTL, and chopping options in the low energy beam transport (LEBT).
Date: August 13, 2004
Creator: Raparia, D.; Alessij.; Beebe-Wang, J. & Weng, W. T.
Object Type: Article
System: The UNT Digital Library
How to study weakly coupled neutral vector bosons (open access)

How to study weakly coupled neutral vector bosons

A weakly coupled new neutral gauge boson, forming a narrow resonance, can be efficiently produced at e{sup +}e{sup -} colliders through radiative return processes if the collider energy is larger than the gauge boson mass. This contribution analyzes the sensitivity of a future linear collider for weakly coupled gauge bosons and briefly discusses how, in case of discovery, its properties can be determined with high precision.
Date: August 13, 2004
Creator: afreitas@fnal.gov, Ayres Freitas
Object Type: Article
System: The UNT Digital Library
Global analysis of inclusive B decays (open access)

Global analysis of inclusive B decays

In light of the large amount of new experimental data, we revisit the determination of |V{sub cb}| and m{sub b} from inclusive semileptonic and radiative B decays. We study shape variables to order {Lambda}{sub QCD}{sup 3}/m{sub b}{sup 3} and {alpha}{sub s}{sup 2}{beta}{sub 0}, and include the order {alpha}{sub s} {Lambda}{sub QCD}/m{sub b} correction to the hadron mass spectrum in semileptonic decay, which improves the agreement with the data. We focus on the 1S and kinetic mass schemes for the b quark, with and without expanding m{sub b}-m{sub c} in HQET. We perform fits to all available data from BABAR, BELLE, CDF, CLEO, and DELPHI, discuss the theoretical uncertainties, and compare with earlier results. We find |V{sub cb}| = (41.9 {+-} 0.6 {+-} 0.1{sub {tau}{sub B}}) x 10{sup -3} and m{sub b}{sup 1S} = 4.68 {+-} 0.04GeV, including our estimate of the theoretical uncertainty in the fit.
Date: August 13, 2004
Creator: Bauer, Christian W.; Ligeti, Zoltan; Luke, Michael; Manohar, Aneesh & Trott, Michael
Object Type: Article
System: The UNT Digital Library
Immiscibility in the NiFe2O4-NiCr2O4 Spinel Binary (open access)

Immiscibility in the NiFe2O4-NiCr2O4 Spinel Binary

The solid solution behavior of the Ni(Fe{sub 1-n}Cr{sub n}){sub 2}O{sub 4} spinel binary is investigated in the temperature range 400-1200 C. Non-ideal solution behavior, as exhibited by non-linear changes in lattice parameter with changes in n, is observed in a series of single-phase solids air-cooled from 1200 C. Air-annealing for one year at 600 C resulted in partial phase separation in a spinel binary having n = 0.5. Spinel crystals grown from NiO, Fe{sub 2}O{sub 3} and Cr{sub 2}O{sub 3} reactants, mixed to give NiCrFeO{sub 4}, by Ostwald ripening in a molten salt solvent, exhibited single phase stability down to about 750 C (the estimated consolute solution temperature, T{sub cs}). A solvus exists below T{sub cs}. The solvus becomes increasingly asymmetric at lower temperatures and extrapolates to n values of 0.2 and 0.7 at 300 C. The extrapolated solvus is shown to be consistent with that predicted using a primitive regular solution model in which free energies of mixing are determined entirely from changes in configurational entropy at room temperature.
Date: August 13, 2004
Creator: Ziemniak, S
Object Type: Article
System: The UNT Digital Library
Chromaticity measurement via the fourier spectrum of transverse oscillations (open access)

Chromaticity measurement via the fourier spectrum of transverse oscillations

Turn-by-turn data from a single BPM includes information on the chromaticity in sidebands displaced above and below the betatron frequency by an amount of the synchrotron frequency. It may be necessary to induce small amplitude synchrotron oscillation by giving the beam a small kick. Power spectrum of the BPM data gives clear chromatic sidebands, and they can be applied to the chromaticity measurement in the Fermilab Booster.
Date: August 13, 2004
Creator: Yang, Xi
Object Type: Report
System: The UNT Digital Library
Report on the Instrument Development Workshop for Biological Imaging Experiments at LCLS (open access)

Report on the Instrument Development Workshop for Biological Imaging Experiments at LCLS

The Linac Coherent Light Source (LCLS) will launch a new era in X-ray science by providing 200 fs pulses of X rays with a peak brightness up to 10 orders of magnitude greater than current sources. One of the most exciting and far-reaching experiments that this new source will enable is single-particle diffraction imaging, whereby atomic-resolution structure of biological macromolecules, complexes, or viruses could be obtained without the need for crystallization. Time-resolved structures and dynamic processes could be studied, with time steps as short as the LCLS pulse duration. Many of the components of a diffraction imaging experiment have been demonstrated individually, such as image reconstruction and electrospray mass-spectrometer particle selection. There are many issues that cannot be resolved until bright pulsed X-ray sources become available in 2005 to test theories. Bringing all the techniques together to field an experiment at LCLS in 2009 is a challenging, but quite feasible, undertaking that requires a coordinated and sustained effort of the community.
Date: August 13, 2004
Creator: Chapman, H; Hajdu, J & Hodgson, K
Object Type: Article
System: The UNT Digital Library
The Effect of UDP-glucuronosyltransferase 1A1 Expression on the Mutagenicity and Metabolism of the Cooked-Food Carcinogen 2-Amino-1-methyl-6-phenylimidazo[4-5,b]pyridine in CHO cells (open access)

The Effect of UDP-glucuronosyltransferase 1A1 Expression on the Mutagenicity and Metabolism of the Cooked-Food Carcinogen 2-Amino-1-methyl-6-phenylimidazo[4-5,b]pyridine in CHO cells

UDP-glucuronosyltransferase proteins (UGT) catalyze the glucuronidation of both endogenous and xenobiotic compounds. In previous studies UGT1A1 has been implicated in the detoxification of certain food-borne-carcinogenic-heterocyclic amines. To determine the importance of UDP-glucuronosyltransferase 1A1 (UGT1A1) in the biotransformation of the cooked-food carcinogen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), genetically modified CHO cells that are nucleotide excision repair-deficient, and express cytochrome P4501A2 (UV5P3 cell line) were transfected with a cDNA plasmid of human UGT1A1 to establish the UDPglucuronosyltransferase 1A1 expressing 5P3hUGT1A1 cell line. Expression of the UGT1A1 gene was verified by screening neogene expressing clonal isolates (G-418 resistant) for their sensitivity to cell killing from PhIP exposure. Five of eleven clones were chosen for further analysis due to their resistance to cell killing. Western blot analysis was used to confirm the presence of the UGT1A1 and CYP1A2 proteins. All five clones displayed a 52 kDa protein band, which corresponded to a UGT1A1 control protein. Only four of the clones had a protein band that corresponded to the CYP1A2 control protein. Correct fragment size of the cDNAs in the remaining 4 clones was confirmed by RT-PCR and quantification of the mRNA product was accomplished by real-time RT-PCR. Expression of UGT1A1 in the transfected cells was 10{sup 4}-10{sup …
Date: August 13, 2004
Creator: Malfatti, M A; Wu, R W & Felton, J S
Object Type: Article
System: The UNT Digital Library
A Low-Cost, Real-Time Network for Radiological Monitoring Around Nuclear Facilities (open access)

A Low-Cost, Real-Time Network for Radiological Monitoring Around Nuclear Facilities

A low-cost, real-time radiological sensor network for emergency response has been developed and deployed at the Lawrence Livermore National Laboratory (LLNL). The Real-Time Radiological Area Monitoring (RTRAM) network is comprised of 16 Geiger-Mueller (GM) sensors positioned on the site perimeter to continuously monitor radiological conditions as part of LLNL's comprehensive environment/safety/health protection program. The RTRAM network sensor locations coincide with wind sector directions to provide thorough coverage of the one square mile site. These low-power sensors transmit measurement data back to a central command center (CCC) computer through the LLNL telecommunications infrastructure. Alarm conditions are identified by comparing current data to predetermined threshold parameters and are validated by comparison with plausible dispersion modeling scenarios and prevailing meteorological conditions. Emergency response personnel are notified of alarm conditions by automatic radio- and computer- based notifications. A secure intranet provides emergency response personnel with current condition assessment data that enable them to direct field response efforts remotely. This system provides a low-cost real-time radiation monitoring solution that is easily converted to incorporate both a hard-wired interior perimeter with strategically positioned wireless secondary and tertiary concentric remote locations. These wireless stations would be configured with solar voltaic panels that provide current to recharge batteries …
Date: August 13, 2004
Creator: Bertoldo, N A
Object Type: Report
System: The UNT Digital Library
Active Vibration Isolation of an Unbalanced Machine Spindle (open access)

Active Vibration Isolation of an Unbalanced Machine Spindle

Proper configurations of controls, sensors, and metrology technologies have enabled precision turning machines to achieve nanometer positioning. However, at this level of positioning resolution, vibration sources can become a limiting factor. One of the largest sources of vibration in a turning machine may be an unbalanced rotating spindle. In this paper, a system is implemented to actively cancel spindle unbalance forces. Specifically, to attenuate the spindle housing vibration using an active vibration control system to prevent the unbalance force from disturbing the rest of the machine systems e.g., the slide servo system or the machine metrology frame. The system controls three degrees of motion. An unbalanced spindle creates a rotating force vector with a once per revolution period. The cause and size of this force is a function of the spindle, the part, the part fixturing, the part setup and the spindle speed. In addition, certain spindle speeds coupled with the size of the unbalance force may contain other harmonics that can excite machine structural resonances. The magnitude of the unbalance force increases as the square of the spindle speed. The control algorithm of this system is fully implemented on a commercially available machine tool controller and is sensitive only …
Date: August 13, 2004
Creator: Hopkins, D J & Geraghty, P
Object Type: Article
System: The UNT Digital Library
Laboratory simulation of cometary x rays using a high-resolution microcalorimeter (open access)

Laboratory simulation of cometary x rays using a high-resolution microcalorimeter

X-ray emission following charge exchange has been studied on the University of California Lawrence Livermore National Laboratory electron beam ion traps EBIT-I and EBIT-II using a high-resolution microcalorimeter. The measured spectra include the K-shell emission from hydrogen-like and helium-like C, N, O, and Ne needed for simulations of cometary x-ray emission. A comparison of the spectra produced in the interaction of O{sup 8+} with N{sub 2} and CH{sub 4} is presented that illustrates the dependence of the observed spectrum on the interaction gas.
Date: August 13, 2004
Creator: Beiersdorfer, P; Chen, H; Boyce, K R; Brown, G V; Kelley, R L; Kilbourne, C A et al.
Object Type: Article
System: The UNT Digital Library
Growth and morphology of 0.80 eV photoemitting indium nitride nanowires (open access)

Growth and morphology of 0.80 eV photoemitting indium nitride nanowires

InN nanowires with high efficiency photoluminescence emission at 0.80 eV are reported for the first time. InN nanowires were synthesized via a vapor solid growth mechanism from high purity indium metal and ammonia. The products consist of only hexagonal wurtzite phase InN. Scanning electron microscopy showed wires with diameters of 50-100nm and having fairly smooth morphologies. High-resolution transmission electron microscopy revealed high quality, single crystal InN nanowires which grew in the <0001> direction. The group-III nitrides have become an extremely important technological material over the past decade. They are commonly used in optoelectronic devices, such as high brightness light-emitting diodes (LEDs) and low wavelength laser diodes (LDs), as well as high power/high frequency electronic devices. Recently InN thin films grown by MOCVD and MBE were found to have a bandgap energy in the range of 0.7-0.9 eV, much lower than the value of {approx}1.9 eV found for InN films grown by sputtering. This large decrease in the direct bandgap transition energy and the ability to form ternary (InGaN) and quaternary (AlInGaN) alloys increases the versatility of group-III nitride optoelectronic devices, ranging from the near IR to the UV. Additionally, InN has some promising transport and electronic properties. It has the …
Date: August 13, 2004
Creator: Johnson, M. C.; Lee, C. J.; Bourret-Courchesne, E. D.; Konsek, S. L.; Aloni, S.; Han, W. Q. et al.
Object Type: Article
System: The UNT Digital Library
A One-dimensional Transient Model of Down-flow Through a Swelling Packed Porous Bed (open access)

A One-dimensional Transient Model of Down-flow Through a Swelling Packed Porous Bed

A transient model of down-flow through an ion exchange column in which the resin swells has been developed. The model is herein described and results are presented. Wall friction can lead to high bed stresses when the resin in columns with high length to diameter ratios swells. These stresses can lead to high and potentially excursive hydraulic pressure drops along a column. A non-dimensional grouping that effectively correlates the final steady-state hydraulic behavior of a column with the resin compressibility, column geometric, and flow parameters has been determined.
Date: August 13, 2004
Creator: SHADDAY, MARTIN
Object Type: Article
System: The UNT Digital Library