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A framework for energy in South Africa with special reference to a long term forecast for energy demand09 February 2015 (has links)
M.Phil. / The construction of mathematical models for making projections of future energy demand is an important step in the formulation of an energy policy for a country or region. In this dissertation the different approaches to energy modelling are investigated. The history of the modelling effort in the world and South Africa is briefly discussed. The development of a comprehensive database is of vital importance for the success of any modelling effort. An energy database for South Africa was developed. An existing energy forecasting model was updated and extended to cover eleven final consuming sectors. Projections of energy demand were made to illustrate the mechanism of the model.
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Analysis of High Switching Frequency Quasi-Z-Source Photovoltaic Inverter Using Wide Bandgap DevicesUnknown Date (has links)
N/A / A Dissertation submitted to the Department of Electrical and Computer Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Summer Semester 2017. / June 12, 2017. / Includes bibliographical references. / Hui Li, Professor Directing Dissertation; Juan Ordonez, University Representative; Chris Edrington, Committee Member; Sastry Pamidi, Committee Member; Thomas A. Lipo, Committee Member.
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Three essays on occupational segregation : women and men in the labor forceAmott, Teresa L. January 1979 (has links)
Thesis (PhD) — Boston College, 1979. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Economics.
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Developing the Polarizable Force Field: Focus on Amino Acid ResiduesSA, QINA 01 September 2011 (has links)
"Polarizable force field has been successfully used in molecular modeling for years, especially in biological and protein simulations. In this research thesis, development of a new polarizable force field ―POSSIM (POlarizable Simulations with Second order Interaction Model) involving electrostatic polarization is described and parameters for several protein residues were produced. In this research thesis, the POSSIM force field was extended to the side chains of the following residues: lysine, glutamic acid, prontonated hisidine, phenylalanine and tryptophan. This work involved producing parameters for methyl ammonium, acetate ion, imidazolium cation, benzene and pyrrole molecules. The parameters fitting procedure starts from the molecular complex with dipolar electrostatic probes of a many-body system to produce polarizabilities, compute the energies, then charges and Lennard-Jones parameters are produced by fitting to gas-phase dimerization calculations, followed by the torsional parameters fitting and end up with the pure liquid simulations. In all the cases, three-body energies, dimerization energies and distances agree well to the accurate quantum mechanical results. The final parameters obtained assured the error of less than 2% in the heat of vaporization and average volume results compared with the available experimental data. Unlike the quantum mechanical calculations, the polarizable force field computations require a relatively small amount of computational resources. Moreover, compared to fixed-charges empirical force fields, polarizable force fields are much more accurate in a number of energy calculations. In the following chapters, the results obtained with this particular polarizable force field are discussed."
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Air Force electronic systems management and the nonprofit corporationsGottleber, Henry A. January 1962 (has links)
Thesis (M.B.A.)--Boston University
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Use of Force and Perceptions of Public Attitude Held by Police TrainersKinsey, Kenneth Lee 01 January 2019 (has links)
Police use-of-force is a topic of interest to most Americans. High-profile shootings of minority citizens and the increase in ambush death rates of police officers has been problematic by dividing society into segments of harsh critics of an entire profession or supporters of the nation's heroes. While use-of-force is highly researched, most existing work has typically forgone the examination of officer mindset in lieu of the more patent explanatory variables of race, sex, and method. The purpose of this study was to gain insight into the psychological influences of officer motivation from those responsible for providing instruction to police officers. This quantitative study focused on perceptions of Public Attitude Towards Police (PATP) as held by police training officers, specifically Academy Instructors (AIs), Departmental Training Officers (DTOs), and Field Training Officers (FTOs) (N = 120). Conflict and organizational theories provided the theoretical foundation for citizen-police conflict, and departmental influence. Data were collected with a Likert scaled questionnaire to discover and present (a) the impacts of perceptions of (PATP) held by police training officers in eleven departments, and (b) variances of those impacts between the three types of trainers. Simple regression analysis revealed a significant statistical impact of use-of-force training by perceptions of PATP by all groups of police trainers, and one-way between groups analysis of variance (ANOVA) revealed a significant difference between impacts of PATP on FTOs in comparison to AIs and DTOs. The present study's results may have a positive impact on social change through the awareness in consideration of mitigating the frequency of use-of-force incidents and increasing safety to law enforcement and the citizenry.
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L'idéologie de Réjean Ducharme d'après "L'hiver de force"Scully, Robert Guy. January 1974 (has links)
No description available.
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Density functional theory of donor-bound multi-exciton complexes in silicon and germaniumPfeiffer, Robert Stanley, January 1981 (has links)
Thesis (Ph. D.)--University of California, San Diego, 1981. / Vita. Bibliography: leaves 100-102.
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Effect of Follower Forces on Aeroelastic Stability of Flexible StructuresChae, Seungmook 09 July 2004 (has links)
Missile bodies and wings are typical examples of structures that can be represented by beam models. Such structures, loaded by follower forces along with aerodynamics, exhibit the vehicle's aeroelastic instabilities. The current research integrates a nonlinear beam dynamics and unsteady aerodynamics to conduct aeroelastic studies of missile bodies and wings subjected to
follower forces. The structural formulations are based on a geometrically-exact, mixed finite element method. Slender-body theory and thin-airfoil theory are used for the missile aerodynamics, and two-dimensional finite-state unsteady aerodynamics is used for wing aerodynamics. The aeroelastic analyses are performed using time-marching scheme for the missile body stability, and eigenvalue analysis for the wing flutter, respectively. Results from the time-marching formulation agree with published results for dynamic stability and show the development of limit cycle oscillations for disturbed flight near and above the critical thrust. Parametric studies of the aeroelastic behavior of specific flexible missile configurations are presented, including effects of flexibility on stability, limit-cycle amplitudes, and missile loads. The results do yield a significant interaction between the thrust, which is a follower force, and
the aeroelastic stability. Parametric studies based on the eigenvalue analysis for the wing
flutter, show that the predicted stability boundaries are very sensitive to the ratio of bending stiffness to torsional stiffness. The effect of thrust can be either stabilizing or
destabilizing, depending on the value of this parameter. An assessment whether or not the magnitude of thrust needed to influence the flutter speed is practical is made for one
configuration. The flutter speed is shown to change by 11% for this specific wing configuration.
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Steady wave drift force on basic objects of symmetryGupta, Anupam 15 May 2009 (has links)
An exponential growth in the offshore industry has resulted in a corresponding increase in
demand for quick, accurate, and implementable designs. With the increase in size of the
structure relative to the wave amplitude, analysis should be performed using the diffraction
theory. The steady wave drift force on a submerged body is a second-order quantity. With a
potential flow assumption, the force arises from the diffraction and radiation of the waves
from the interaction with the body. For a fixed body in waves the steady force is
contributed from the wave diffraction effect alone. Numerical solutions for are generally
needed for the computation of the steady drift force on submerged structures. In this study
the steady wave drift forces on several fixed bodies of basic shapes are derived in closed
form. The thesis addresses the steady drift forces on the following basic structures: a box, a
vertical circular cylinder, a submerged horizontal cylinder, a bottom-seated horizontal half
cylinder, a bottom-seated hemisphere, a submerged sphere, and an ellipsoid. The results
developed demonstrate the importance of various independent non-dimensional parameters.
To achieve speed and accuracy of the analytical/numerical solutions for the second order forces on the basic bodies with symmetry has been presented. Mathematical
formulation of the boundary value problem and its second order solution have been
described using the different coordinates depending on the symmetry and nature of the
object. Charts and formulas have been developed to provide solution for the second order
wave forces on different basic structures like cylinder, sphere and ellipsoids. This study is
helpful for a first pass estimate of the steady drift force where the translational and
rotational contributions are neglected. The illustrative examples provide a sense of the
accuracy and an approach to bound the results of complex geometries by approximating
them as simpler geometries.
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