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The History of the Bill J. Priest Institute for Economic Development of the Dallas County Community College District

Description: The Bill J. Priest Institute for Economic Development is an entity created in the Dallas County Community College District to serve the community in workforce and economic development. The history of the Priest Institute over the last ten years parallels and illustrates the commitment of community colleges nationally to workforce and economic development. The history also reflects similar goals and trends within the state of Texas and, particularly, in the city of Dallas. The Priest Institute i… more
Date: April 1994
Creator: Hughes, Martha
Partner: UNT Libraries
open access

A calorimetric measurement of the strong coupling constant in electron-positron annihilation at a center-of-mass energy of 91.6 GeV

Description: In this work, a measurement of the strong coupling constant {alpha}{sub s} in e{sup +}e{sup {minus}} annihilation at a center-of-mass energy of 91.6 GeV is presented. The measurement was performed with the SLD at the Stanford Linear Collider facility located at the Stanford Linear Accelerator Center in California. The procedure used consisted of measuring the rate of hard gluon radiation from the primary quarks in a sample of 9,878 hadronic events. After defining the asymptotic manifestation of… more
Date: April 1, 1994
Creator: Martirena, S. G.
Partner: UNT Libraries Government Documents Department
open access

High resolution electron diffraction analysis of structural changes associated with the photocycle of bacteriorhodopsin

Description: Changes in protein structure that occur during the formation of the M photointermediate of bacteriorhodopsin can be directly visualized by electron diffraction techniques. Samples containing a high percentage of the M intermediate were trapped by rapidly cooling the crystals with liquid nitrogen following illumination with filtered green light at 240K and 260K respectively. Difference Fourier projection maps for M minus bR at two temperatures and for M{sub 260K} minus M{sub 240K} are presented.… more
Date: April 1, 1994
Creator: Han, B.-G.
Partner: UNT Libraries Government Documents Department
open access

The crosswell electromagnetic response of layered media

Description: Crosswell electromagnetic measurements are a promising new geophysical technique for mapping subsurface electrical conductivity which can provide information about the subsurface distribution of water, oil or steam. In this work the fields from a low frequency vertical magnetic dipole have been examined from the specific point of view of their application to the determination of the conductivity of a layered medium. The source and the receiver were placed inside two separate boreholes. The rang… more
Date: April 1, 1994
Creator: Deszcz-Pan, M.
Partner: UNT Libraries Government Documents Department
open access

Support minimized inversion of acoustic and elastic wave scattering

Description: This report discusses the following topics on support minimized inversion of acoustic and elastic wave scattering: Minimum support inversion; forward modelling of elastodynamic wave scattering; minimum support linearized acoustic inversion; support minimized nonlinear acoustic inversion without absolute phase; and support minimized nonlinear elastic inversion.
Date: April 24, 1994
Creator: Safaeinili, A.
Partner: UNT Libraries Government Documents Department
open access

The mechanism of the oligomerization of thiophene-based para-quinodimethanes

Description: For the last decade, the Trahanovsky research group has focused on the study of various reactive molecules such as o-quinodimethanes (o-QDM`s) and p-quinodimethanes (p-QDM`s) derived from benzene, furan, and thiophene. These types of molecules are reactive and dimerize or polymerize at room temperature. One of the group`s interests is to understand the dimerization mechanism of these molecules. Paper 1 describes the preparation and dimerization product analyses of 2-ethylidene-5-methylene-2,5-d… more
Date: April 24, 1994
Creator: Wang, Yili
Partner: UNT Libraries Government Documents Department
open access

The analysis and minimization of oxygen contamination in the powder processing of molybdenum disilicide

Description: Problems with MoSi{sub 2} include low-temperature fracture toughness, high-temperature creep resistance, and ``pest`` phenomena. Oxygen introduced by powder processing may be the cause of some of these problems. This study led to the following conclusions: Supplied powders have significant oxygen present prior to processing (up to 2.5 %), in the form of silica on the surface. This oxygen contamination did not increase by exposure to air at room temperature. An improved powder processing method … more
Date: April 24, 1994
Creator: Shannon, K.
Partner: UNT Libraries Government Documents Department
open access

Topics in the structure of hadronic systems

Description: In this dissertation the author examines a variety of different problems in the physics of strongly-bound systems. Each is elucidated by a different standard method of analysis developed to probe the properties of such systems. He begins with an examination of the properties and consequences of the current algebra of weak currents in the limit of heavy quark spin-flavor symmetry. In particular, he examines the assumptions in the proof of the Ademollo-Gatto theorem in general and for spin-flavor… more
Date: April 1, 1994
Creator: Lebed, R. F.
Partner: UNT Libraries Government Documents Department
open access

Flavor symmetries and fermion masses

Description: We introduce several ways in which approximate flavor symmetries act on fermions and which are consistent with observed fermion masses and mixings. Flavor changing interactions mediated by new scalars appear as a consequence of approximate flavor symmetries. We discuss the experimental limits on masses of the new scalars, and show that the masses can easily be of the order of weak scale. Some implications for neutrino physics are also discussed. Such flavor changing interactions would easily er… more
Date: April 1, 1994
Creator: Rasin, A.
Partner: UNT Libraries Government Documents Department
open access

Theory and modelling of quench in cable-in-conduit superconducting magnets

Description: A new simple, self consistent theoretical model is presented that describes the phenomena of quench propagation in Cable-In-Conduit superconducting magnets. The model (Quencher) circumvents many of the difficulties associated with obtaining numerical solutions in more general existing models. Specifically, a factor of 30-50 is gained in CPU time over the general, explicit time dependent codes used to study typical quench events. The corresponding numerical implementation of the new model is des… more
Date: April 1, 1994
Creator: Shajii, A.
Partner: UNT Libraries Government Documents Department
open access

Recursive recovery of Markov transition probabilities from boundary value data

Description: In an effort to mathematically describe the anisotropic diffusion of infrared radiation in biological tissue Gruenbaum posed an anisotropic diffusion boundary value problem in 1989. In order to accommodate anisotropy, he discretized the temporal as well as the spatial domain. The probabilistic interpretation of the diffusion equation is retained; radiation is assumed to travel according to a random walk (of sorts). In this random walk the probabilities with which photons change direction depend… more
Date: April 1, 1994
Creator: Patch, S. K.
Partner: UNT Libraries Government Documents Department
open access

Magnetic metallic multilayers

Description: Utilizing self-consistent Hartree-Fock calculations, several aspects of multilayers and interfaces are explored: enhancement and reduction of the local magnetic moments, magnetic coupling at the interfaces, magnetic arrangements within each film and among non-neighboring films, global symmetry of the systems, frustration, orientation of the various moments with respect to an outside applied field, and magnetic-field induced transitions. Magnetoresistance of ferromagnetic-normal-metal multilayer… more
Date: April 1, 1994
Creator: Hood, R. Q.
Partner: UNT Libraries Government Documents Department
open access

A passively-safe fusion reactor blanket with helium coolant and steel structure

Description: Helium is attractive for use as a fusion blanket coolant for a number of reasons. It is neutronically and chemically inert, nonmagnetic, and will not change phase during any off-normal or accident condition. A significant disadvantage of helium, however, is its low density and volumetric heat capacity. This disadvantage manifests itself most clearly during undercooling accident conditions such as a loss of coolant accident (LOCA) or a loss of flow accident (LOFA). This thesis describes a new he… more
Date: April 1, 1994
Creator: Crosswait, K. M.
Partner: UNT Libraries Government Documents Department
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