The dissertation research will comprise three essays on the topic of the resource curse hypothesis and its mechanisms. The phenomenon of low economic growth in resource-rich regions is recognized as the “resource curse”. These essays will contribute to an understanding of the regional resource-growth relation within a nation. Essay one tests the resource curse hypothesis at the U.S. state level. With a system of equations model, I decompose the overall resource effect to account for the two leading explanations — crowding-out and institution effects, thus investigate whether the institutions mediate the crowding-out effects. I did not find evidence of an overall negative effect on growth by resource wealth. Both the crowding-out and institution appear present, but they offset: the resource boom crowds out industrial investments, but good institutions mitigate the overall effect. Resources do reduce growth in states with low-quality institutions, including Louisiana, Oklahoma, and Texas. Essay two compares the effects of resource revenues on the economic growth and growth-related factors across Chinese provinces and American states, using panel data from 1990 to 2015. With the Instrumental Variable (IV) strategy, I show that regions with higher resource revenues grow faster than other regions in both China and the U.S. The positive resource effect is larger and more statistically significant in the U.S. Further testing impacts of three resource-related policies in China, e.g. the market price reform, the fiscal reform, and the Western Development Strategy, I show that the market price reform together with the privatization process on coal resources contribute the positive resource effect in China. Though strong and positive resource – growth relations appear in both countries, evidence also suggests consistent negative resource effects on certain growth-related factors in both countries, such as educational attainments and R&D activities. Essay three explores the schooling response to the oil and gas boom, taking advantage of timing and spatial variation in oil and gas well drilling activities. Development of cost-reducing technologies at the time of higher crude oil and natural gas prices in the early 2000s has accelerated shale oil and gas extraction in the United States. I show that intensive drilling activities have decreased grade 11 and 12 enrollment over the 14 year study window − approximately 36 fewer students per county on average and overall, 41,760 fewer students across the 15 states enrolled considered in the analysis. On average, with one additional oil or gas well drilled per thousand initial laborers, grade 11 and 12 enrollment would decrease 0.24 percent at the county level, all else equal. I investigate heterogeneous effects and show that the implied effect of the boom is larger in states with a younger compulsory schooling age requirement (16 years of age instead of 17 or 18), lower state-level effective tax rate on oil and gas productions, traditional mining, non-metro, and persistent poverty counties.

Pas de résumé / Propagation of nonlinear acoustic waves in inhomogeneous media is an important problem inmany research domains of modern theoretical and applied acoustics. For example, studies onpropagation of high amplitude N-waves in turbulent atmosphere are relevant to the sonic boomproblem which involves high interest due to development of new civil supersonic aircrafts. Inrelation to sonic boom problem, many studies on spark-generated N-wave propagation through aturbulent layer were carried out in model laboratory-scale experiments which are more controlledand reproducible than field measurements. Propagation of high intensity focused ultrasound intissue (HIFU) is intensively studied for medical applications. HIFU is a basis of new surgicaldevices for noninvasive thermal and mechanical ablation of tumors.In this thesis, the problem of characterization of high amplitude N-waves generated in air byan electric spark was studied using combined acoustical and optical methods. The fine structureof shocks was deduced from the shadowgraphy images with a resolution that cannot be obtainedusing condenser microphones. It was shown that the combination of optical and acoustical methodsallows complete characterization of the N-waves.N-wave propagation through a layer of thermal turbulence was further studied in a laboratoryexperiment. The evolution of statistical distributions and average values of the most importantN-wave parameters was investigated at different propagation distances. Experimental results werecompared to data obtained in another experiment known in literature, where N-wave was propagatedthrough kinematic turbulence. It was shown that in the case of almost the same widths ofthe turbulent layers, values of the characteristic scales and rms of refractive index fluctuations, thekinematic turbulence leads to stronger distortions of the peak pressure and the shock rise time ofthe N-wave and to 2-3 greater probabilities to observe intense focusing in caustics.Effects of nonlinear propagation and random focusing on the statistics of N-wave amplitudewere studied theoretically using the KZK equation and the phase screen model. The phase screenwas characterized by the correlation length and the refraction length – the distance where firstcaustics occur. Probability distributions, mean values and standard deviations of the N-wave peakpressure were obtained from the numerical solutions and were presented as functions of the propagationdistance and the nonlinear length. Statistical results from the KZK model were comparedwith analytical predictions of the nonlinear geometrical acoustics approach (NGA). It was shown,that NGA approach is valid only up to the distance of one third of refraction length of the screen.Strong nonlinear effects were shown to suppress amplitude fluctuations. The effect of the scale ofinhomogeneities on amplitude statistics was also investigated.The problem of focusing of ultrasound beam through inhomogeneous medium is importantfor medical diagnostics and nondestructive testing problems. The inhomogeneities of biologicaltissue or of industrial materials can destroy beam focusing. In the thesis, distortions of a weaklynonlinear diagnostic beam focused through a phase layer of special configuration were consideredexperimentally and theoretically. Feasibility of selective destruction of focusing of differentharmonics in the beam was predicted in the modeling and confirmed in experiment.The most modern HIFU devices rely on using two-dimensional multi-element phased arrayswith elements randomly distributed over a segment of a spherical surface. Numerical experimentis an important tool to characterize pressure fields created by HIFU radiators. Intensity levels atthe focus of HIFU radiators can reach several tens of thousands of W/cm2, causing nonlinearpropagation effects and formation of shocks [...]

M.Phil. / Although a great deal of research has been conducted on diversity management in South Africa, very little of this research has focused on age diversity within interactive information societies such as libraries in South Africa. This study will focus specifically on academic libraries. It is also clear that most of the research regarding age diversity within Academic Information Services (AIS) has focused on managing the difference in ages between library patrons and library staff members. Very little of the research is devoted to age diversity between co-workers, and even less research has been conducted regarding Cuspers as a generational cohort within the library environment. This study is aimed at investigating age diversity within AIS in South Africa in relation to its effect on work, work performance and co-worker relationships. It is also aimed at encouraging organisations, and specifically AIS, to take cognisance of the current age demographic of their libraries and to develop and implement not only succession planning policies, but also relevant recruitment and retention policies in order to avoid employee and leadership vacuums. The research findings of this study are relevant as they give organisations in general, and specifically AIS within higher education institutions (HEI), a point of reference to guide the formulation of recruitment and employment policies that would appeal to the values and preferences of younger generational cohorts currently under-represented in these organisations. In addition, this study is of value with regard to the formulation of succession policies focused on the planning and training of new middle and top management staff members in order to improve current succession policies and plans.

The diploma thesis deals with the design of a mobile crane for working in a manufacturing environment. The crane has load capacity 600 kg, length of radius 3 m and load-lifting height 3m. It is equipped with the electric chain hoist with electric trolley, rotation by held by hand of burden. The diploma thesis contains crane design and control and design calculations of important components. Technical drawings are also part of the thesis.

This diploma thesis deals with the construction design of revolving column crane which is used for manipulation with metal plates for metal shears and bending bench. The aim is to set main proportions and basic parameters for the designed steel construction via design calculation. Then the thesis deals with checking of strength analysis done by programme I-DEAS NX 11. Suggestion of disposal placement of the crane, choice of hoist, travelling system, auxiliary device and drawing documentation are also parts of the design.

Field studies were conducted to test three application methods for applying antagonistic herbicide combinations: 1) tank mix (TMX), 2) mix-in-line (MIL), and 3) separate boom (SPB). Sethoxydim applied with bentazon, glyphosate applied with dicamba or 2,4-D, and clethodim applied with dicamba or 2,4-D had higher efficacy when applied using the SPB method. Antagonism of all the herbicide combinations above was observed when applied using the TMX and MIL methods. In some cases, antagonism was avoided when using the SPB method. Three application methods tested in greenhouse studies were 1) TMX, 2) synthetic auxin applied first (AAF), and 3) synthetic auxin applied second (AAS). The AAS application method resulted in higher weed control than the TMX and AAF methods. Analysis done through liquid chromatography mass spectrometry supported the greenhouse results with higher rates of glyphosate detected with the AAS method.

The care of the elderly is a growing problem. Existing services are inadequate for the needs of an aging population. In order to suggest new services to deal with the care of the elderly, this report examined four areas: the demographic characteristics of our aging society, the nature of services in general, services provided to the elderly population, and the application of role theory to the caregiver/care recipient dyad. Role theory identified conflicts felt by both the caregiver and care recipient. These conflicts were explored in three sets of focus group interviews: women 65 years old and older, women familiar with the experience of primary caregiver, and women between the ages of 23 and 42 (the age range representative of the Baby Boom cohort). Information from these interviews was used to understand both current and future perceptions of the elderly and of the role of caregivers in this society and what services they perceive are necessary for the elderly to function independently in this society. / Master of Science

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Recent progresses by the aircraft industry in the development of a quieter supersonic transport have opened the possibility of overland supersonic flights, which are currently banned by aviation authorities in most countries. For the ban to be lifted, the sonic booms the aircraft generate at supersonic speed must be acceptable from a human-perception point of view, in particular inside buildings. The problem of the transmission of sonic booms inside buildings can be divided in several aspects such as the external pressure loading, structure vibration, and interior acoustic response. Past investigations on this problem have tackled all these aspects but were limited to simple structures and often did not account for the coupled fluid-structure interaction. A more comprehensive work that includes all the effects of sonic booms to ultimately predict the noise exposure inside realistic building structures, e.g. residential houses, has never been reported. Thus far, these effects could only be investigated experimentally, e.g. flight tests. In this research, a numerical model and a computer code are developed within the above context to predict the vibro-acoustic response of simplified building structures exposed to sonic booms, at low frequency. The model is applicable to structures with multiple rectangular cavities, isolated or interconnected with openings. The response of the fluid-structure system, including their fully coupled interaction, is computed in the time domain using a modal-decomposition approach for both the structural and acoustic systems. In the dynamic equations, the structural displacement is expressed in terms of summations over the "in vacuo" normal modes of vibration. The interior pressure is expressed in terms of summations over the acoustic modes of the rooms with perfectly reflecting surfaces (hard walls). This approach is simple to implement and computationally efficient at low frequency, when the modal density is relatively low. The numerical model is designed specifically for this application and includes several novel formulations. Firstly, a new shell finite-element is derived to model the structural components typically used in building construction that have orthotropic characteristics such as plaster-wood walls, floors, and siding panels. The constitutive matrix for these types of components is formulated using simple analytical expressions based on the orthotropic constants of an equivalent orthotropic plate. This approach is computationally efficient since there is no need to model all the individual subcomponents of the assembly (studs, sheathing, etc.) and their interconnections. Secondly, a dedicated finite-element module is developed that implements the new shell element for orthotropic components as well as a conventional shell element for isotropic components, e.g. window panels and doors. The finite element module computes the "in vacuo" structural modes of vibration. The modes and external pressure distribution are then used to compute modal loads. This dedicated finite-element module has the main advantage of overcoming the need, and subsequent complications, for using a large commercial finite-element program. Lastly, a novel formulation is developed for the fully coupled fluid-structure model to handle room openings and compute the acoustic response of interconnected rooms. The formulation is based on the Helmholtz resonator approach and is applicable to the very low frequency-range, when the acoustic wavelength is much larger than the opening dimensions. Experimental validation of the numerical model and computer code is presented for three test cases of increasing complexity. The first test structure consists of a single plaster-wood wall backed by a rigid rectangular enclosure. The structure is excited by sonic booms generated with a speaker. The second test structure is a single room made of plaster-wood walls with two double-panel windows and a door. The third test structure consists of the first room to which a second room with a large window assembly was added. Several door configurations of the structure are tested to validate the formulation for room openings. This latter case is the most realistic one as it involves the interaction of several structural components with several interior cavities. For the last two test cases, sonic booms with realistic durations and amplitudes were generated using an explosive technique. Numerical predictions are compared to the experimental data for the three test cases and show a good overall agreement. Finally, results from a parametric study are presented for the case of the single wall backed by a rigid enclosure. The effects of sonic-boom shape, e.g. rise time and duration, and effects of the structure geometry on the fluid-structure response to sonic booms are investigated. / Ph. D.