• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1554
  • 340
  • 233
  • 197
  • 197
  • 197
  • 197
  • 197
  • 196
  • 162
  • 97
  • 34
  • 23
  • 21
  • 19
  • Tagged with
  • 3412
  • 1485
  • 879
  • 875
  • 870
  • 600
  • 295
  • 278
  • 237
  • 219
  • 205
  • 186
  • 128
  • 124
  • 123
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

'Even' in Comparative Structures

Cronin, Melissa 01 August 2022 (has links)
In typical distributions (Even [John] was late), 'even' projects two expected presuppositions: 1) There are more people than John who were late and 2) John is a surprising candidate to be late. In comparatives (John is even later than Sam), there is a unique inference, which is distinct from the two aforementioned and, critically, unique to the context of comparatives. In this case, we could say that John and Sam are both late, which is not entailed from the simple comparative ‘John is later than Sam’ (Rett, 2008). The aim of this thesis is to relate the expected presuppositions (Karttunen and Peters, 1979), which constitute the broad theoretical framing of ‘even’, to the unique inference borne from comparatives. Doing so brings two research questions. First, the syntactic element that 'even' focuses must be identified. Departing from Barker (1991), I argue this syntactic element, in many comparatives with 'even', is the structure obligatorily elided under the process of Comparative Deletion (Bresnan 1973, 1975). A key argument against Barker is on the grounds of discourse. The second research question pertains to satisfying the two expected presuppositions of ‘even’, which, in turn, situates the distribution under study within the larger theoretical framing of ‘even’. Together, the arguments for both questions give an explanation as to how the unique inference is derived.
232

Precision Light Flavor Physics from Lattice QCD

Murphy, David James January 2017 (has links)
In this thesis we present three distinct contributions to the study of light flavor physics using the techniques of lattice QCD. These results are arranged into four self-contained papers. The first two papers concern global fits of the quark mass, lattice spacing, and finite volume dependence of the pseudoscalar meson masses and decay constants, computed in a series of lattice QCD simulations, to partially quenched SU(2) and SU(3) chiral perturbation theory (χPT). These fits determine a subset of the low energy constants of chiral perturbation theory — in some cases with increased precision, and in other cases for the first time — which, once determined, can be used to compute other observables and amplitudes in χPT. We also use our formalism to self-consistently probe the behavior of the (asymptotic) chiral expansion as a function of the quark masses by repeating the fits with different subsets of the data. The third paper concerns the first lattice QCD calculation of the semileptonic K0 → π −` +ν` (K`3) form factor at vanishing momentum transfer, f Kπ + (0), with physical mass domain wall quarks. The value of this form factor can be combined with a Standard Model analysis of the experimentally measured K0 → π −` +ν` decay rate to extract a precise value of the Cabibbo-Kobayashi-Maskawa (CKM) matrix element Vus, and to test unitarity of the CKM matrix. We also discuss lattice calculations of the pion and kaon decay constants, which can be used to extract Vud through an analogous Standard Model analysis of experimental constraints on leptonic pion and kaon decays. The final paper explores the recently proposed exact one flavor algorithm (EOFA). This algorithm has been shown to drastically reduce the memory footprint required to simulate single quark flavors on the lattice relative to the widely used rational hybrid Monte Carlo (RHMC) algorithm, while also offering modest O(20%) speed-ups. We independently derive the exact one flavor action, explore its equivalence to the RHMC action, and demonstrate that additional preconditioning techniques can be used to significantly accelerate EOFA simulations. We apply EOFA to the ongoing RBC/UKQCD calculation of the ∆I = 1/2 K → ππ decay amplitude, and demonstrate that, in this context, gauge field configurations can be generated a factor of 4.2 times faster using an EOFAbased simulation rather than the previous RHMC-based simulations. We expect that EOFA will help to significantly reduce the statistical error in the first-principles determination of the Standard Model CP-violation parameters ε and ε′ offered by the K → ππ calculation.
233

A study of charm quark production in beauty quark decays with the OPAL detector at LEP /

Waller, David, January 1900 (has links)
Thesis (Ph. D.)--Carleton University, 2003. / Includes bibliographical references (p. 138-146). Also available in electronic format on the Internet.
234

Measurement of the strange-antistrange asymmetry at NLO in QCD from NuTeV dimuon data /

Mason, David Alexander, January 2006 (has links)
Thesis (Ph.D.)--University of Oregon, 2006. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 415-429). Also available for download via the World Wide Web; free to University of Oregon users.
235

The study of elementary particle events using a computer-controlled system

Lawrence, D. E. January 1967 (has links)
No description available.
236

Effects of Nanoclay and Conductive Carbon Black on Morphology Development in Chaotic Mixing of Immiscible Polymers

Dharaiya, Dhawal January 2006 (has links)
No description available.
237

COARSE-GRAINED MC SIMULATIONS OF POLYMER NANOCOMPOSITES

Erguney, Fatih M. 02 October 2007 (has links)
No description available.
238

Detection of Low Energy Particles

Harvey, Stanley B. January 1976 (has links)
Part A of two Project Reports: The other part is designated Part B: Industrial Project / <p>The channel electron multiplier is a radiation detector suitable for the detection of 0.1-100 keV electrons and atomic particles. Studies were made to determine channeltron absolute efficiency as a function of input particle rate, time, and incident energy. The efficiency for electrons was found to vary from 90% for 1 keV electrons to 50% for 4 keV electrons. The channeltron efficiency was found to depend strongly on input rate below 50 counts per second. Although the cause of this discrepency is unclear, a possible explanation was developed involving the secondary emission coefficient of the detector multiplying surface. The channeltron was subsequently used to detect secondary electrons from gold foil bombarded with both electrons and protons. By scattering the incident. particles from a gold foil, the number of secondary electrons generated was found to vary linearly with energy from 2 to 11 keV. The possibility exists for use of the foil-channeltron detector to count neutral atomic particles with known efficiency. This has been a difficult problem in the past. </p> / Thesis / Master of Engineering (MEngr)
239

The Observed Stability of PVC Particles in n-Butylchloride

Bhola, Krishnadatt 07 1900 (has links)
<p> The mechanism by which PVC particles remained stable in n-butylchloride was investigated.</p> <p> The PVC particles were made by aqueous emulsion polymerization with benzoyl peroxide initiator and polyvinyl alcohol surfactant. The particles were cleaned by ion exchange and their surface charge was found to be 0.068 ± 0.005 C/m^2. Dispersions of PVC in n-butylchloride were prepared by two methods. In the first, the particles were dried in an oven. The dried particles were redispersed in n-butylchloride via sonication. This produced a dispersion consisting of 0.26 kg/m^3 of PVC particles with an arithmetic volume average diameter of 317 nm and a standard deviation of 93 nm. The second method involved dialyzing the cleaned aqueous latex with methanol and then with n-butylchloride. The dialysis method was inferior to the sonication method. The dialysis method was time consuming, it produced a dispersion with large particle diameter, the dispersion was contaminated with water and methanol and surface species were removed by the methanol.</p> <p> The particles were found to be stabilized by an electrostatic mechanism. This was verified by observing that the particles migrated to the positive electrode when exposed to a potential difference of 1000 V. A surface potential of 0.203 V was calculated for the particles from mobility measurements and the Huckel equation.</p> <p> The charge separation that must occur to allow the particles to have the negative charge is hypothesized to be a result of organic molecules such as PVC-PVA oligomers that dissolve from the particles and form micelles. These molecules were readily soluble in methanol and only slightly soluble in n-butylchloride. As a result, when the dispersion was washed with methanol, the particles flocculated. The presence of these species in the dispersant was supported by evidence from ultra-violet, infra-red and nuclear magnetic resonance spectroscopy. The electronegative groups in the micelles provide a reasonably polar environment for hydrogen ions to exist. These hydrogen ions became the countercharge for the negatively charged particles.</p> / Thesis / Master of Engineering (MEngr)
240

Concentration gradient patterns of traffic and non-traffic generated aerosols: Ultrafine, PM2.5, and coarse particles

Sparks, Christopher S. 26 September 2011 (has links)
No description available.

Page generated in 0.0272 seconds