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A Quantitative Study of the Presidential Search Process and Position Longevity in Community Colleges

A Quantitative Study of the Presidential Search Process and Position Longevity in Community Colleges

Date: December 2011
Creator: Howells, Constance L.
Description: A great deal of time, money, and effort can be expended on hiring community college presidents without any assurance that they will remain in their new positions a substantial amount of time. Building on decades of literature reporting the continuing decrease of presidential longevity, this study examined the methods most successful in selecting presidents with relatively greater longevity and what relationship exists between the type of presidential search used and the length of tenure. An original 18-question survey was e-mailed to 904 community college and two-year institution presidents to capture information about both current and previous presidencies. Participants returned 224 valid responses for a response rate of 24.8%. Results of a generalized linear model (GLM) yielded a statistically significant result showing a positive relationship between the variable Q7STDT1(type of presidential searches in current position) and length of tenure of selected candidates (F = 3.41, p = .006).No significant relationship was found between the selection process used in the immediately previous presidential positions and selected candidates’ longevity in those positions. Information from this study can be used to decide what types of selection process should be used and to indicate further topics of inquiry in this area.
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Quantization Dimension for Probability Definitions

Quantization Dimension for Probability Definitions

Access: Use of this item is restricted to the UNT Community.
Date: December 2001
Creator: Lindsay, Larry J.
Description: The term quantization refers to the process of estimating a given probability by a discrete probability supported on a finite set. The quantization dimension Dr of a probability is related to the asymptotic rate at which the expected distance (raised to the rth power) to the support of the quantized version of the probability goes to zero as the size of the support is allowed to go to infinity. This assumes that the quantized versions are in some sense ``optimal'' in that the expected distances have been minimized. In this dissertation we give a short history of quantization as well as some basic facts. We develop a generalized framework for the quantization dimension which extends the current theory to include a wider range of probability measures. This framework uses the theory of thermodynamic formalism and the multifractal spectrum. It is shown that at least in certain cases the quantization dimension function D(r)=Dr is a transform of the temperature function b(q), which is already known to be the Legendre transform of the multifractal spectrum f(a). Hence, these ideas are all closely related and it would be expected that progress in one area could lead to new results in another. It would ...
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Quantization Of Spin Direction For Solitary Waves in a Uniform Magnetic Field

Quantization Of Spin Direction For Solitary Waves in a Uniform Magnetic Field

Date: May 2003
Creator: Hoq, Qazi Enamul
Description: It is known that there are nonlinear wave equations with localized solitary wave solutions. Some of these solitary waves are stable (with respect to a small perturbation of initial data)and have nonzero spin (nonzero intrinsic angular momentum in the centre of momentum frame). In this paper we consider vector-valued solitary wave solutions to a nonlinear Klein-Gordon equation and investigate the behavior of these spinning solitary waves under the influence of an externally imposed uniform magnetic field. We find that the only stationary spinning solitary wave solutions have spin parallel or antiparallel to the magnetic field direction.
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Quantized Hydrodynamics

Quantized Hydrodynamics

Date: August 1972
Creator: Coomer, Grant C.
Description: The object of this paper is to derive Landau's theory of quantized hydrodynamics from the many-particle Schroedinger equation. Landau's results are obtained, together with an additional term in the Hamiltonian.
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Quantum-Confined CdS Nanoparticles on DNA Templates

Quantum-Confined CdS Nanoparticles on DNA Templates

Date: May 1998
Creator: Rho, Young Gyu
Description: As electronic devices became smaller, interest in quantum-confined semiconductor nanostructures increased. Self-assembled mesoscale semiconductor structures of II-VI nanocrystals are an especially exciting subject because of their controllable band gap and unique photophysical properties. Several preparative methods to synthesize and control the sizes of the individual nanocrystallites and the electronic and optical properties have been intensively studied. Fabrication of patterned nanostructures composed of quantum-confined nanoparticles is the next step toward practical applications. We have developed an innovative method to fabricate diverse nanostructures which relies on the size and a shape of a chosen deoxyribonucleic acid (DNA) template.
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Quantum Perspectives on Physical and Inorganic Chemistry

Quantum Perspectives on Physical and Inorganic Chemistry

Date: December 2007
Creator: Grimes-Marchan, Thomas V.
Description: Applications of computational quantum chemistry are presented, including an analysis of the photophysics of cyclic trinuclear coinage metal pyrazolates, an investigation into a potential catalytic cycle utilizing transition metal scorpionates to activate arene C-H bonds, and a presentation of the benchmarking of a new composite model chemistry (the correlation consistent composite approach, ccCA) for the prediction of classical barrier heights. Modeling the pyrazolate photophysics indicates a significant geometric distortion upon excitation and the impact of both metal identity and substituents on the pyrazolates, pointing to ways in which these systems may be used to produce rationally-tuned phosphors. Similarly, thermodynamic and structural investigations into the catalyst system points to promising candidates for clean catalytic activation of arenes. The ccCA was found to reproduce classical reaction barriers with chemical accuracy, outperforming all DFT, ab initio, and composite methods benchmarked.
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Quasi-Three Dimensional Experiments on Liquid-Solid Fluidized Bed of Three Different Particles in Two Different Distributors

Quasi-Three Dimensional Experiments on Liquid-Solid Fluidized Bed of Three Different Particles in Two Different Distributors

Date: December 2009
Creator: Obuseh, Chukwuyem Charles
Description: This thesis is an experimental study of the fluidization of binary mixture in particulate flows. A fluidized bed with two distributors was built with water being used as carrying fluid. Three types of solid particles of nylon, glass and aluminum of the same size and different densities are used in the experiments. The wall effect on a single particle fluidization, the fluidization of binary mixture of large density difference (nylon and aluminum of density ratio of 0.42), and the fluidization of binary mixture of close density (glass and aluminum with density ratio of 0.91) were investigated. Also, the effect of distributors on mono-disperse and bi-disperse particle fluidization was investigated. Results show that the presence of narrow walls reduces the minimum fluidization velocity for a single particle by as much as nearly 40%. Also, in the case of binary mixture of close density particles, uniform mixing was easily achieved and no segregation was observed, but in the case of large density difference particles, there exists significant segregation and separation. At high velocity, the uniform distributor behaves like a transport bed. To achieve a full bed in the single jet, it requires 1.5 times velocity of the uniform distributor. This behavior determines ...
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Quaternion Representation of Crystal Point Groups

Quaternion Representation of Crystal Point Groups

Date: August 1959
Creator: West, Richard Harrison
Description: The physical behavior of crystalline solids is very closely related to the internal symmetry of the crystal structure. For this reason it is desirable to represent mathematically this symmetry in such a way that the actual physical problems can be handled as they arise. In the case of this thesis the research has been guided by a list of desired properties for such a representation. No claim is made that the list is complete.
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Quaternion Representation of Crystal Space Groups

Quaternion Representation of Crystal Space Groups

Date: January 1961
Creator: Hufstetler, Thomas Jerry
Description: This investigation is designed to find quaternion operators which will generate selected space groups and which are more convenient to manipulate in some important types of problems.
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A Quenchofluorometric Study of Polycyclic Aromatic Hydrocarbons in Molecularly Organized Media

A Quenchofluorometric Study of Polycyclic Aromatic Hydrocarbons in Molecularly Organized Media

Date: May 1998
Creator: Pandey, Siddharth
Description: Detection, identification and separation of polycyclic aromatic compounds in environmental samples are of extreme importance since many of these compounds are well known for their potential carcinogenic and/or mutagenic activities. Selective quenching of molecular fluorescence can be utilized effectively to analyze mixtures containing different polycyclic aromatic hydrocarbons. Molecularly organized assemblies are used widely in detection and separation of these compounds mainly because of less toxicity and enhanced solubilization capabilities associated with these media. Feasibility of using nitromethane and the alkylpyridinium cation as selective fluorescence quenching agents for discriminating between alternant versus nonalternant polycyclic aromatic hydrocarbons (PAHs) is critically examined in several molecularly organized micellar solvent media. Fluorescence quenching is used to probe the structural features in mixed micelles containing the various combinations of anionic, cationic, nonionic and zwitterionic surfactants. Experimental results provide valuable information regarding molecular interactions between the dissimilar surfactants.
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