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Epicyclic Twin-helix Magnetic Structure for Parametric-resonance Ionization Cooling

Description: Para­met­ric-res­o­nance Ion­iza­tion Cool­ing (PIC) is en­vi­sioned as the final 6D cool­ing stage of a high-lu­mi­nos­i­ty muon col­lid­er. Im­ple­ment­ing PIC im­pos­es strin­gent con­straints on the cool­ing chan­nel's mag­net­ic op­tics de­sign. This paper pre­sents a lin­ear op­tics so­lu­tion com­pat­i­ble with PIC. Our so­lu­tion con­sists of a su­per­po­si­tion of two op­po­site-he­lic­i­ty equal-pe­ri­od and equal-strength he­li­cal dipole har­mon­ics and a straight nor­mal quadrupole… more
Date: May 1, 2010
Creator: A. Afanasev, R.P. Johnson, Y.S. Derbenev, V.S. Morozov
Partner: UNT Libraries Government Documents Department
open access

Progress of Bep Treatments on Nb at JLAB

Description: Recent experimental results have indicated that Buffered Electropolishing (BEP) is a promising candidate for the next generation of surface treatment technique for Nb superconducting radio frequency (SRF) cavities to be used in particle accelerators. In order to lay the foundation for using BEP as the next generation surface treatment technique for Nb SRF cavities, some fundamental aspects of BEP treatments for Nb have to be investigated. In this report, recent progress on BEP study at JLab is … more
Date: May 1, 2010
Creator: A.T. Wu, S. Jin, R.A. Rimmer,X.Y. Lu, K. Zhao
Partner: UNT Libraries Government Documents Department
open access

Can Data Recognize Its Parent Distribution?

Description: This study is concerned with model selection of lifetime and survival distributions arising in engineering reliability or in the medical sciences. We compare various distributions, including the gamma, Weibull and lognormal, with a new distribution called geometric extreme exponential. Except for the lognormal distribution, the other three distributions all have the exponential distribution as special cases. A Monte Carlo simulation was performed to determine sample sizes for which survival dis… more
Date: May 1, 1999
Creator: A.W.Marshall; J.C.Meza & Olkin, and I.
Partner: UNT Libraries Government Documents Department
open access

Microstructure, Phase Formation, and Stress of Reactively-Deposited Metal Hydride Thin Films

Description: This document summarizes research of reactively deposited metal hydride thin films and their properties. Reactive deposition processes are of interest, because desired stoichiometric phases are created in a one-step process. In general, this allows for better control of film stress compared with two-step processes that react hydrogen with pre-deposited metal films. Films grown by reactive methods potentially have improved mechanical integrity, performance and aging characteristics. The two reac… more
Date: May 1, 2002
Creator: ADAMS, DAVID P.; ROMERO, JUAN A.; RODRIGUEZ, MARK A.; FLORO, JERROLD A. & KOTULA, PAUL G.
Partner: UNT Libraries Government Documents Department
open access

Representative volume size: A comparison of statistical continuum mechanics and statistical physics

Description: In this combination background and position paper, the authors argue that careful work is needed to develop accurate methods for relating the results of fine-scale numerical simulations of material processes to meaningful values of macroscopic properties for use in constitutive models suitable for finite element solid mechanics simulations. To provide a definite context for this discussion, the problem is couched in terms of the lack of general objective criteria for identifying the size of the… more
Date: May 1, 1999
Creator: AIDUN,JOHN B.; TRUCANO,TIMOTHY G.; LO,CHI S. & FYE,RICHARD M.
Partner: UNT Libraries Government Documents Department
open access

Molecular dynamic simulations, {sup 6}Li solid state NMR and ultraphosphate glasses

Description: The author's laboratory continues to use NMR to investigate the structure and dynamics in amorphous materials, including the local structure of ultraphosphate glasses. Changes in the alkali environment in these phosphate glasses as a function of modifier concentration has recently been probed using {sup 6}Li and {sup 23}Na solid state NMR. Molecular dynamic (MD) simulations have also been performed in an attempt to gain additional insight into the variations of the local structure. Interestingl… more
Date: May 1, 2000
Creator: ALAM,TODD M.
Partner: UNT Libraries Government Documents Department
open access

THERMAL CONDUCTIVITY AND OTHER PROPERTIES OF CEMENTITIOUS GROUTS

Description: The thermal conductivity and other properties cementitious grouts have been investigated in order to determine suitability of these materials for grouting vertical boreholes used with geothermal heat pumps. The roles of mix variables such as water/cement ratio, sand/cement ratio and superplasticizer dosage were measured. In addition to thermal conductivity, the cementitious grouts were also tested for bleeding, permeability, bond to HDPE pipe, shrinkage, coefficient of thermal expansion, exothe… more
Date: May 1, 1998
Creator: ALLAN,M.
Partner: UNT Libraries Government Documents Department
open access

Cloud to CAD

Description: This paper documents work performed to convert scanned range data to CAD solid model representation. The work successfully developed surface fitting algorithms for quadric surfaces (e.g. plane, cone, cylinder, and sphere), and a segmentation algorithm based entirely on surface type, rather than on a differential metric like Gaussian curvature. Extraction of all CAD-required parameters for quadric surface representation was completed. Approximate face boundaries derived from the original point c… more
Date: May 1, 2001
Creator: AMES,ARLO L.
Partner: UNT Libraries Government Documents Department
open access

OPTIMUM ENERGY ABSORPTION OF A SHORT-PULSE LASER IN A DOPED DIELECTRIC SLAB

Description: 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 c… more
Date: May 1, 2001
Creator: ANG, L.
Partner: UNT Libraries Government Documents Department
open access

Blade Manufacturing Improvement: Remote Blade Manufacturing Demonstration

Description: 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 temp… more
Date: May 1, 2003
Creator: ASHWILL, THOMAS D.
Partner: UNT Libraries Government Documents Department
open access

Cost Study for Large Wind Turbine Blades

Description: 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 s… more
Date: May 1, 2003
Creator: ASHWILL, THOMAS D.
Partner: UNT Libraries Government Documents Department
open access

Laser Safety Audit and Inventory System Database

Description: 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… more
Date: May 1, 2003
Creator: AUGUSTONI, ARNOLD L.
Partner: UNT Libraries Government Documents Department
open access

The comparison of element partitioning in two types of thermal treatment facilities and the effects on potential radiation dose

Description: 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… more
Date: May 1, 1995
Creator: Aaberg, R. L.; Burger, L. L.; Baker, D. A.; Wallo, A., III; Vazquez, G. A. & Beck, W. L.
Partner: UNT Libraries Government Documents Department
open access

Porosity in millimeter-scale welds of stainless steel : three-dimensional characterization.

Description: 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… more
Date: May 1, 2012
Creator: Aagesen, Larry K. & Madison, Jonathan D.
Partner: UNT Libraries Government Documents Department
open access

Search for the Flavor Changing Neutral Current Decay t $\to Zq$ in $p \bar{p}$ Collisions at $\sqrt{s}=1.96$

Description: 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 identifie… more
Date: May 1, 2008
Creator: Aaltonen, : T.
Partner: UNT Libraries Government Documents Department
open access

Combined Tevatron upper limit on gg -> H -> W^+W^- and constraints on the Higgs boson mass in fourth-generation fermion models

Description: We combine results from searches by the CDF and D0 collaborations for a standard model Higgs boson (H) in the process gg {yields} H {yields} W{sup +}W{sup -} in p{bar p} collisions at the Fermilab Tevatron Collider at {radical}s = 1.o6 TeV. With 4.8 fb{sup -1} of itnegrated luminosity analyzed at CDF and 5.4 fb{sup -1} at D0, the 95% Confidence Level upper limit on {sigma}(gg {yields} H) x {Beta}(H {yields} W{sup +}W{sup -}) is 1.75 pb at m{sub H} = 120 GeV, 0.38 pb at m{sub H} = 165 GeV, and 0… more
Date: May 1, 2010
Creator: Aaltonen, T.; Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M. et al.
Partner: UNT Libraries Government Documents Department
open access

First Observation of Vector Boson Pairs in a Hadronic Final State at the Tevatron Collider

Description: We present the first observation in hadronic collisions of the electroweak production of vector boson pairs (VV, V = W,Z) where one boson decays to a dijet final state. The data correspond to 3.5 fb{sup -1} of integrated luminosity of p{bar p} collisions at {radical}s = 1.96 TeV collected by the CDF II detector at the Fermilab Tevatron. We observe 1516 {+-} 239(stat) {+-} 144(syst) diboson candidate events and measure a cross section {sigma}(p{bar p} {yields} VV + X) of 18.0 {+-} 2.8(stat) {+-}… more
Date: May 1, 2009
Creator: Aaltonen, T.; Adelman, Jahred A.; Akimoto, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, Dante E. et al.
Partner: UNT Libraries Government Documents Department
open access

Observation of the Omega(b)- Baryon and Measurement of the Properties of the Xi(b)- and Omega(b)- Baryons

Description: The authors report the observation of the bottom, doubly-strange baryon {Omega}{sub b}{sup -} through the decay chain {Omega}{sub b}{sup -} {yields} J/{psi}{Omega}{sup -}, where J/{psi} {yields} {mu}{sup +} {mu}{sup -}, {Omega}{sup -} {yields} {Lambda}K{sup -}, and {Lambda} {yields} p {pi}{sup -}, using 4.2 fb{sup -1} of data from p{bar p} collisions at {radical}s = 1.96 TeV, and recorded with the Collider Detector at Fermilab. A signal is observed whose probability of arising from a background… more
Date: May 1, 2009
Creator: Aaltonen, T.; Adelman, Jahred A.; Akimoto, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, Dante E. et al.
Partner: UNT Libraries Government Documents Department
open access

Production of psi(2S) Mesons in p anti-p Collisions at 1.96-TeV

Description: The authors have measured the differential cross section for the inclusive production of {psi}(2S) mesons decaying to {mu}{sup +}{mu}{sup -} that were produced in prompt or B-decay processes from p{bar p} collisions at 1.96 TeV. These measurements have been made using a data set from an integrated luminosity of 1.1 fb{sup -1} collected by the CDF II detector at Fermilab. For events with transverse momentum p{sub T}({psi}(2S)) > 2 GeV/c and rapidity |y({psi}(2S))| < 0.6 we measure the inte… more
Date: May 1, 2009
Creator: Aaltonen, T.; Adelman, Jahred A.; Akimoto, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, Dante E. et al.
Partner: UNT Libraries Government Documents Department
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