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  • 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.
11

No longer a myth: A study of the happy and healthy marriages of African American male professional athletes

Dees, J.E.M.E.G. Vann 01 May 2007 (has links)
The marriages of professional athletes have been examined for years, but the positive factors in those marriages have rarely been examined. This study focuses on the factors that contribute to the strength and happiness in the marriages of professional athletes. Five professional athletes and their wives were interviewed in effort to determine the factors that contributed to the strength of their marriages. Open communication, shared values, religion/faith, and trust were consistently found to be important components contributing to the strength of these marriages. This study adds to the limited literature available discussing the positive aspects of professional athlete marriagess / Master of Science
12

Exact relations for strongly interacting fermions

Hofmann, Johannes Benedict January 2014 (has links)
No description available.
13

Some general properties of entropy for homogeneous systems

Kay, Amanda R. January 2000 (has links)
No description available.
14

Functional and dynamic rheological properties of wheat gluten

Khatkar, Bhupendar Singh January 1996 (has links)
No description available.
15

Vibronic coupling in tetrahedral and icosahedral systems

Rough, Stephen Michael January 1998 (has links)
No description available.
16

Electron dynamics in high-intensity laser fields

Harvey, Christopher January 2010 (has links)
We consider electron dynamics in strong electromagnetic fields, such as those expected from the next generation of high-intensity laser facilities. Beginning with a review of constant classical fields, we demonstrate that the electron motion (as given by the Lorentz force equation) can be divided into one of four Lorentz invariant cases. Parameterising the field tensor in terms of a null tetrad, we calculate the radiative energy spectrum for an electron in crossed fields. Progressing to an infinite plane wave, we demonstrate how the electron orbit in the average rest frame changes from figure-of-eight to circular as the polarisation changes from linear to circular. To move beyond a plane wave one must resort to numerics. We therefore present a novel numerical formulation for solving the Lorentz equation. Our scheme is manifestly covariant and valid for arbitrary electromagnetic field configurations. Finally, we reconsider the case of an infinite plane wave from a strong field QED perspective. At high intensities we predict a substantial redshift of the usual kinematic Compton edge of the photon emission spectrum, caused by the large, intensity dependent effective mass of the electrons inside the laser beam. In addition, we find that the notion of a centre-of-mass frame for a given harmonic becomes intensity dependent.
17

A SPECTROSCOPIC SURVEY OF THE FIELDS OF 28 STRONG GRAVITATIONAL LENSES: THE GROUP CATALOG

Wilson, Michelle L., Zabludoff, Ann I., Ammons, S. Mark, Momcheva, Ivelina G., Williams, Kurtis A., Keeton, Charles R. 16 December 2016 (has links)
With a large, unique spectroscopic survey in the fields of 28 galaxy-scale strong gravitational lenses, we identify groups of galaxies in the 26 adequately sampled fields. Using a group-finding algorithm, we find 210 groups with at least 5 member galaxies; the median number of members is 8. Our sample spans redshifts of 0.04 <= z(grp) <= 0.76 with a median of 0.31, including 174 groups with 0.1 < z(grp) < 0.6 The groups have radial velocity dispersions of 60 <= sigma(grp) <= 1200 km s(-1) with a median of 350 km s(-1). We also discover a supergroup in field B0712+472 at z = 0.29 that consists of three main groups. We recover groups similar to similar to 85% of those previously reported in these fields within our redshift range of sensitivity and find 187 new groups with at least five members. The properties of our group catalog, specifically, (1) the distribution of sgrp, (2) the fraction of all sample galaxies that are group members, and (3) the fraction of groups with significant substructure, are consistent with those for other catalogs. The distribution of group virial masses agrees well with theoretical expectations. Of the lens galaxies, 12 of 26 (46%) (B1422+231, B1600+434, B2114+022, FBQS J0951+2635, HE0435-1223, HST J14113+5211, MG0751+2716, MGJ1654+1346, PG 1115+080, Q ER 0047-2808, RXJ1131-1231, and WFI J2033-4723) are members of groups with at least five galaxies, and one more (B0712+472) belongs to an additional, visually identified group candidate. There are groups not associated with the lens that still are likely to affect the lens model; in six of 25 (24%) fields (excluding the supergroup), there is at least one massive (sigma(grp) >= 500 km s(-1)) group or group candidate projected within 2' of the lens.
18

A walk through superstring theory with an application to Yang-Mills theory: k-strings and D-branes as gauge/gravity dual objects

Stiffler, Kory M 01 July 2010 (has links)
Superstring theory is one current, promising attempt at unifying gravity with the other three known forces: the electromagnetic force, and the weak and strong nuclear forces. Though this is still a work in progress, much effort has been put forth toward this goal. A set of specific tools which are used are gauge/gravity dualities. This thesis consists of a specific implementation of gauge/gravity dualities to describe k-strings of strongly coupled gauge theories as objects dual to Dpbranes embedded in confining supergravity backgrounds from low energy superstring field theory. Along with superstring theory, k-strings are also commonly investigated with lattice gauge theory and Hamiltonian methods. A k$string is a colorless combination of quark-anti-quark source pairs, between which a color flux tube develops. The two most notable terms of the k-string energy are, for large quark anti-quark separation L, the tension term, proportional to L, and the Coulombic 1/L correction, known as the Luscher term. This thesis provides an overview of superstring theories and how gauge/gravity dualities emerge from them. It shows in detail how these dualities can be used for the specific problem of calculating the k-string energy in 2+1 and 3+1 space-time dimensions as the energy of Dp-branes in the dual gravitational theory. A detailed review of k-string tension calculations is given where good agreement is found with lattice gauge theory and Hamiltonian methods. In reviewing the k-string tension, we also touch on how different representations of k-strings can be described with Dp-branes through gauge/gravity dualities. The main result of this thesis is how the Luscher term is found to emerge from the energy calculation of Dp-branes. In 2+1 space-time dimensions, we have Luscher term data to compare with from lattice gauge theory, where we find good agreement.
19

Older Men Working it Out A strong face of ageing and disability

Fleming, Alfred Andrew January 2001 (has links)
This hermeneutical study interprets and describes the phenomena of ageing and living with disability. The lived experiences of 14 older men and the horizon of this researcher developed an understanding of what it is like for men to grow old and, for some, to live with the effects of a major disability. The study is grounded in the philosophical hermeneutics of Gadamer and framed in the context of embodiment, masculinity, and narrative. I conducted multiple in-depth interviews with older men aged from 67 to 83 years of age. Seven of the participants had experienced a stroke and I was able to explore the phenomenon of disability with them. Through thematic and narrative analyses of the textual data interpretations were developed that identified common meanings and understandings of the phenomena of ageing and disability. These themes and narratives reveal that the men�s understandings are at odds with conventional negative views of ageing and disability. These older men are �alive and kicking�, they voice counternarratives to the dominant construction of ageing as decline and weakness, and have succeeded in remaking the lifeworld after stroke. Overall I have come to understand an overarching meaning of older men �working it out� as illustrative of a strong face of ageing and disability. Older men seek out opportunities to participate actively in community life and, despite the challenges of ageing and disability, lead significant and meaningful lives. These findings challenge and extend our limited understandings of men�s experiences of ageing and living with disability. This interpretation offers gendered directions for policy development, clinical practice, and future research.
20

High Resolution Sculpting and Imaging of Ultracold Neutral Plasmas

McQuillen, Patrick 06 September 2012 (has links)
The sculpting of ultracold neutral plasmas represents a frontier in the experimental study of collective modes in strongly coupled plasmas. By extending the range of accessible length scales to less than tens of microns we gain access to a regime where The sculpting of ultracold neutral plasmas represents a frontier in the experimental study of collective modes in strongly coupled plasmas. By extending the range of accessible length scales to less than tens of microns we gain access to a regime where strong coupling's effects are predicted yet largely untested. To this effort, high resolution optical systems were designed, bench tested and implemented for sculpting and imaging ultracold neutral plasmas. Many complications and unexpected effects were documented to assist future experimental design considerations, including, those due to saturation and optical thickness, both of which limit the utility of 461 nm push beam modulations. It was concluded that sculpting should be performed on the 412 nm ionizing beam and real-time density space analysis is reliable for spatial frequencies up to 5 cyc/mm by using 4X magnified imaging. Higher spatial frequencies benefit from velocity space analysis due to extremely fast dynamics and low intensity levels.

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