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ENGINEERING OF THE AGS SNAKE COIL ASSEMBLY.
A 30% Snake superconducting magnet is proposed to maintain polarization in the AGS proton beam, the magnetic design of which is described elsewhere. The required helical coils for this magnet push the limits of the technology developed for the RHIC Snake coils. First, fields must be provided with differing pitch along the length of the magnet. To accomplish this, a new 3-D CAD system (''Pro/Engineer'' from PTC), which uses parametric techniques to enable fast iterations, has been employed. Revised magnetic field calculations are then based on the output of the mechanical model. Changes are made in turn to the model on the basis of those field calculations. To ensure that accuracy is maintained, the final solid model is imported directly into the CNC machine programming software, rather than by the use of graphics translating software. Next, due to the large coil size and magnetic field, there was concern whether the structure could contain the coil forces. A finite element analysis was performed, using the 3-D model, to ensure that the stresses and deflections were acceptable. Finally, a method was developed using ultrasonic energy to improve conductor placement during coil winding, in an effort to minimize electrical shorts due to conductor …
Date:
May 12, 2003
Creator:
ANERELLA,M. GUPTA,R. KOVACH,P. MARONE,A. PLATE,S. POWER,K. SCHMALZLE,J. WILLEN,E.
Object Type:
Article
System:
The UNT Digital Library
OPTIMUM ENERGY ABSORPTION OF A SHORT-PULSE LASER IN A DOPED DIELECTRIC SLAB
A model is used to calculate energy absorption efficiency when a short-pulse laser impinges on a dielectric slab doped with an impurity for which the electrons have a resonant line at the laser wavelength. The amount of the energy resonant absorption is due to the overlapping between laser spectrum and resonance spectrum. The energy absorption efficiency can be maximized for a certain degree of doping concentration (at a given pulselength) and also for a certain pulselength (at a given doping concentration). For a modest amount of impurity, the resonant absorption may increase the fraction of energy absorption up to tens of percent of laser energy at 100s optical cycles when the laser wavelength is tuned within 1% of the resonant line. Dimensionless parameters are constructed so that the scaling to various parameters: laser wavelength, laser pulselength, dielectric constant, slab thickness, impurity concentration, resonant linewidth, and separation between the laser wavelength and the line resonance, could easily be obtained.
Date:
May 1, 2001
Creator:
ANG, L.
Object Type:
Article
System:
The UNT Digital Library
Blade Manufacturing Improvement: Remote Blade Manufacturing Demonstration
The objective of this program was to investigate manufacturing improvements for wind turbine blades. The program included a series of test activities to evaluate the strength, deflection, performance, and loading characteristics of the prototype blades. The original contract was extended in order to continue development of several key blade technologies identified in the project. The objective of the remote build task was to demonstrate the concept of manufacturing wind turbine blades at a temporary manufacturing facility in a rural environment. TPI Composites successfully completed a remote manufacturing demonstration in which four blades were fabricated. The remote demonstration used a manufacturing approach which relied upon material ''kits'' that were organized in the factory and shipped to the site. Manufacturing blades at the wind plant site presents serious logistics difficulties and does not appear to be the best approach. A better method appears to be regional manufacturing facilities, which will eliminate most of the transportation cost, without incurring the logistical problems associated with fabrication directly onsite. With this approach the remote facilities would use commonly available industrial infrastructure such as enclosed workbays, overhead cranes, and paved staging areas. Additional fatigue testing of the M20 root stud design was completed with good results. …
Date:
May 1, 2003
Creator:
ASHWILL, THOMAS D.
Object Type:
Report
System:
The UNT Digital Library
Cost Study for Large Wind Turbine Blades
The cost study for large wind turbine blades reviewed three blades of 30 meters, 50 meters, and 70 meters in length. Blade extreme wind design loads were estimated in accordance with IEC Class I recommendations. Structural analyses of three blade sizes were performed at representative spanwise stations assuming a stressed shell design approach and E-glass/vinylester laminate. A bill of materials was prepared for each of the three blade sizes using the laminate requirements prepared during the structural analysis effort. The labor requirements were prepared for twelve major manufacturing tasks. TPI Composites developed a conceptual design of the manufacturing facility for each of the three blade sizes, which was used for determining the cost of labor and overhead (capital equipment and facilities). Each of the three potential manufacturing facilities was sized to provide a constant annual rated power production (MW per year) of the blades it produced. The cost of the production tooling and overland transportation was also estimated. The results indicate that as blades get larger, materials become a greater proportion of total cost, while the percentage of labor cost is decreased. Transportation costs decreased as a percentage of total cost. The study also suggests that blade cost reduction efforts …
Date:
May 1, 2003
Creator:
ASHWILL, THOMAS D.
Object Type:
Report
System:
The UNT Digital Library
DETERMINING THE RATIO OF THE H+ YIELDS TV TO H+ YIELDS TB DECAY RATES FOR LARGE TAN BETA AT THE LARGE HADRON COLLIDER.
We present results on the determination of the observable ratio R = BR(H{sup +} {yields} {tau}{sup +}{nu}{sup -})/BR(H{sup +} {yields} t{bar b}) of charged Higgs boson decay rates as a discriminant quantity between Supersymmetric and non-Supersymmetric models. Simulation of measurements of this quantity through the analysis of the charged Higgs production process gb {yields} tbH{sup +} and relative backgrounds in the two above decay channels has been performed in the context of ATLAS. A {approx} 12-14% accuracy on R can be achieved for tan {beta} = 50, m{sub H{sup {+-}}} = 300-500 GeV and after an integrated luminosity of 300 fb{sup -1}. With this precision measurement, the Large Hadron Collider (LHC) can easily discriminate between models for the two above scenarios, so long as tan {beta} > 20.
Date:
May 27, 2003
Creator:
ASSAMAGAN,K. A. GUASCH,J. MORETTI,S. PENARANDA,S.
Object Type:
Article
System:
The UNT Digital Library
Charged Higgs bosons in the transition region M{sub H{sup {+-}}} {approx} m{sub t} at the LHC
We illustrate preliminary results obtained through Monte Carlo (HERWIG) and detector (ATLFAST) simulations of the H{sup {+-}} {yields} {tau}{sup {+-}}{nu}{sub {tau}} signature of charged Higgs bosons with masses comparable to that of the top quark.
Date:
May 25, 2003
Creator:
ASSAMAGAN,K. A. GUCHAIT,M. MORETTI,S.
Object Type:
Article
System:
The UNT Digital Library
Hydrogen Storage Properties of the Tetrahydrofuran Treated Magnesium
The electronic structure, crystalline feature and morphology of the tetrahydrofuran (THF) treated magnesium, along with its hydriding and dehydriding properties have been investigated. The THF treated magnesium absorbs 6.3 wt per cent hydrogen at 723K and 3.5 MPa. After hydrogenation, in addition to the expected MgH2, a new less-stable hydride phase appears at 673K, but not at a lower temperature. Desorption produces 5.5 wt per cent hydrogen at 723K against a back pressure of 1.3 Pa after 20 cycles of hydriding-dehydriding. The THF treatment improves the kinetics of hydrogen absorption and desorption significantly. From 723K to 623K, the THF treated Mg demonstrates acceptable reaction rates. XPS studies show that tetrahydrofuran treatment causes the electronic energy state of the magnesium surface atoms to change, but the XRD studies show the crystal structure remains unchanged. Metallographic observation of the bulk hydrides of THF treated magnesium reveal they are poly-crystalline wi th the wide-spreading slip bands and twins within the crystals, indicating the phase transformation upon hydriding causes serious stress and distortion. It appears this microstructural deformation explains the much higher energy requirements (higher pressure and temperature) for magnesium hydrogenation than the simple lattice expansion that accompany hydrogen uptake for LaNi5 and FeTi.
Date:
May 25, 2004
Creator:
AU, MING
Object Type:
Article
System:
The UNT Digital Library
Laser Safety Audit and Inventory System Database
A laser safety auditing and inventory system has been in use at Sandia National Laboratories--Albuquerque for the past five years and has recently been considered for adoption by Sandia National Laboratories--Livermore. The system utilizes the ''Microsoft Access'' database application, part of the Office 2000 software package. Audit and inventory data is available on-line for ready access by laser users. Data is updated weekly to provide users with current information relating to laser facility audits and laser inventories.
Date:
May 1, 2003
Creator:
AUGUSTONI, ARNOLD L.
Object Type:
Report
System:
The UNT Digital Library
The comparison of element partitioning in two types of thermal treatment facilities and the effects on potential radiation dose
The US Department of Energy (DOE) is performing a technical analysis to support the potential development of risk-based, numerical radiological control criteria (RCC) for mixed waste from DOE operations. As part of the technical analysis, potential future radiation doses are being calculated for workers at thermal treatment facilities and members of the public residing near such facilities. This study compared two types of thermal treatment systems: a conventional combustion chamber with excess air, represented by a rotary kiln with afterburner, and an oxygen-deficient pyrolysis unit, represented by a plasma arc furnace. The purpose of the first part of this study is to estimate the partitioning for significant radionuclides and elements in the two types of thermal treatment systems. Excess-air systems are generally found to produce heavy-metal chlorides, oxides, and sulfates; plasma-arc systems tend to produce more volatile free metals. This difference causes a change in source term dominance from halide volatility to free metal volatility. Chemical thermodynamic methodology is used to estimate partitioning in the two treatment systems. The second part of the study examines how the potential radiation dose to workers handling residue materials is affected by partitioning of radionuclides at the different types of facilities.
Date:
May 1, 1995
Creator:
Aaberg, R. L.; Burger, L. L.; Baker, D. A.; Wallo, A., III; Vazquez, G. A. & Beck, W. L.
Object Type:
Report
System:
The UNT Digital Library
ALARA Analysis of Radiological Control Criteria Associated with Alternatives for Disposal of Hazardous Wastes
This ALARA analysis of Radiological Control Criteria (RCC) considers alternatives to continued storage of certain DOE mixed wastes. It also considers the option of treating hazardous wastes generated by DOE facilities, which have a very low concentration of radionuclide contaminants, as purely hazardous waste. Alternative allowable contaminant levels examined correspond to doses to an individual ranging from 0.01 mrem/yr to 10 to 20 mrem/yr. Generic waste inventory data and radionuclide source terms are used in the assessment. Economic issues, potential health and safety issues, and qualitative factors relating to the use of RCCs are considered.
Date:
May 15, 2002
Creator:
Aaberg, Rosanne L.; Bilyard, Gordon R.; Branch, Kristi M.; Lavender, Jay C. & Miller, Peter L.
Object Type:
Report
System:
The UNT Digital Library
Measurement of $D^{* /-}$ Meson Production in Jets from Pp Collisions at Sqrt(S) = 7 TeV with the ATLAS Detector
None
Date:
May 6, 2013
Creator:
Aad, Georges
Object Type:
Article
System:
The UNT Digital Library
Measurement of the Inclusive and Dijet Cross-sections of b-jets in pp Collisions at sqrt(s) = 7 TeV with the ATLAS Detector
None
Date:
May 28, 2013
Creator:
Aad, Georges
Object Type:
Article
System:
The UNT Digital Library
Measurement of the Inclusive Isolated Prompt Photon Cross-Section in $Pp$ Collisions at $\sqrt{s}=7$ TeV Using 35 Pb-1 of ATLAS Data
None
Date:
May 31, 2013
Creator:
Aad, Georges
Object Type:
Article
System:
The UNT Digital Library
Measurement of the Inclusive $W^\pm$ and Z/Gamma Cross Sections in the Electron and Muon Decay Channels in $Pp$ Collisions at $\sqrt{s}=7$ TeV with the ATLAS Detector
None
Date:
May 29, 2013
Creator:
Aad, Georges
Object Type:
Article
System:
The UNT Digital Library
Measurement of the Pseudorapidity and Transverse Momentum Dependence of the Elliptic Flow of Charged Particles in Lead-Lead Collisions at $\sqrt{s_{NN}}=2.76$ TeV with the ATLAS Detector
None
Date:
May 31, 2013
Creator:
Aad, Georges
Object Type:
Article
System:
The UNT Digital Library
Search for a Heavy Neutral Particle Decaying Into an Electron and a Muon Using 1 Fb^-1 of ATLAS Data
None
Date:
May 30, 2013
Creator:
Aad, Georges
Object Type:
Article
System:
The UNT Digital Library
Search for Extra Dimensions Using Diphoton Events in 7 TeV Proton-Proton Collisions with the ATLAS Detector
None
Date:
May 7, 2013
Creator:
Aad, Georges
Object Type:
Article
System:
The UNT Digital Library
Search for Massive Long-lived Highly Ionising Particles with the ATLAS Detector at the LHC
None
Date:
May 29, 2013
Creator:
Aad, Georges
Object Type:
Article
System:
The UNT Digital Library
Search for New Phenomena in ttbar Events with Large Missing Transverse Momentum in Proton-Proton Collisions at sqrt(s)=7$ TeV With the ATLAS Detector
None
Date:
May 29, 2013
Creator:
Aad, Georges
Object Type:
Article
System:
The UNT Digital Library
Search for Pair Production of First Or Second Generation Leptoquarks in Proton-Proton Collisions at sqrt(s)=7 TeV using the ATLAS detector at the LHC
None
Date:
May 21, 2013
Creator:
Aad, Georges
Object Type:
Article
System:
The UNT Digital Library
Search for Strong Gravity Signatures in Same-Sign Dimuon Final States Using the ATLAS Detector at the LHC
None
Date:
May 20, 2013
Creator:
Aad, Georges
Object Type:
Article
System:
The UNT Digital Library
Search for Supersymmetry in Final States With Jets, Missing Transverse Momentum And One Isolated Lepton in Sqrt{s} = 7 TeV Pp Collisions Using 1 $Fb^{-1}$ of ATLAS Data
None
Date:
May 28, 2013
Creator:
Aad, Georges
Object Type:
Article
System:
The UNT Digital Library
Porosity in millimeter-scale welds of stainless steel : three-dimensional characterization.
A variety of edge joints utilizing a continuous wave Nd:YAG laser have been produced and examined in a 304-L stainless steel to advance fundamental understanding of the linkage between processing and resultant microstructure in high-rate solidification events. Acquisition of three-dimensional reconstructions via micro-computed tomography combined with traditional metallography has allowed for qualitative and quantitative characterization of weld joints in a material system of wide use and broad applicability. The presence, variability and distribution of porosity, has been examined for average values, spatial distributions and morphology and then related back to fundamental processing parameters such as weld speed, weld power and laser focal length.
Date:
May 1, 2012
Creator:
Aagesen, Larry K. & Madison, Jonathan D.
Object Type:
Report
System:
The UNT Digital Library
Search for the Flavor Changing Neutral Current Decay t $\to Zq$ in $p \bar{p}$ Collisions at $\sqrt{s}=1.96$
We report a search for the flavor changing neutral current (FCNC) decay of the top quark t {yields} Zq (q = u, c) in p{bar p} collisions at {radical}s = 1.96 TeV using a data sample corresponding to an integrated luminosity of 1.9 fb{sup -1} collected by the CDF II detector. This decay is strongly suppressed in the standard model (SM) and a signal at the Tevatron would be an indication of physics beyond the SM. Using Z+ {ge} 4 jet final state candidate events, both with and without an identified bottom quark jet, we discriminate signal from background by exploring kinematic constraints present in FCNC events and obtain an upper limit of {Beta}(t {yields} Zq) < 3.7% at 95% C.L.
Date:
May 1, 2008
Creator:
Aaltonen, : T.
Object Type:
Article
System:
The UNT Digital Library