Saudi Cultural Missions Theses & Dissertations
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Item Restricted Essays on Sustainable Growth and Development in GCC Countries(Howard University, 2024-06-28) Alamri, Aisha; Kato, MikaThis article analyzes the effects of natural resources and location determinants on foreign direct investment (FDI) in the Gulf Cooperation Countries (GCC) using panel data from 2000–2022. Using oil production, oil reserves, and oil production in relation to oil reserves as a means to measure natural resources, I determine fixed effect (FE) and random effect (RE) analyses based on the Hausman test. This study concluded that oil production, and oil production relative to oil reserves discouraged FDI in GCC countries. Furthermore, the study concludes that there is a positive relationship between oil prices, infrastructure, and FDI, while human capital has no influence on FDI.42 0Item Restricted Modelling Crystallisation in Polymers(University of Sheffield, 2024-06-03) Algethami, Rasha; Clarke, NigelIn this thesis, we introduce the development of a computational model, combining a coarse-grained phase field approach with hydrodynamics using the Stokes equation under low Reynold's number conditions. This innovative model successfully elucidates the growth patterns of rhombus-shaped single crystals in polymers driven by chemical potential gradients and fluid flow. Unlike traditional methods, this study treats the single crystal as a highly viscous fluid, employing fluid-particle dynamics, thereby eliminating the need for intricate boundary conditions at the crystal-fluid interface. The investigation commences with the development of a finite difference-based phase field model, enabling the simulation of polymer crystal growth from a simple melt. The model adapts two thermodynamic driving forces to account for the meta-stable phases in crystallisation. This model allows for the exploration of diverse crystal morphologies, including circular, rectangular, and rhombus shapes. In depth analysis of isotropic and anisotropic interfacial energies reveals their significant influence on crystal growth rates and shapes. Moreover, the study extends to the interaction between adjacent single crystals, uncovering merging processes and growth rates under constant and non-constant interface mobility. A key aspect of this research lies in the validation of the model, performed within a simple shear flow system. This validation not only ensures the model's accuracy but also offers insights into the complicated relationship between fluid flow and crystal rotation. Through simulations, the study showed how different flow conditions impact polymer crystal rotation rates and patterns. Furthermore, the study delves into the role of interface thickness and interfacial energy on crystal motion and growth dynamics. By altering the interface thickness over time and maintaining it constant in other instances, the study reveals noticeable effects on crystal rotation and growth. The results show that crystal rotation increases significantly with changing interface thickness compared to the case where the interface thickness remains constant. However, the crystal growth exhibits a considerable increase where the interface thickness remains fixed. Additionally, variations in interfacial energy along different directions are shown to influence crystal rotation and growth rates significantly. The research also introduces a theoretical framework explaining crystal rotation driven by induced asymmetrical flow in a polymer melt. The theoretical predictions, when compared with computational simulations, are considered satisfactory, despite slight disparities attributed to specific assumptions.11 0Item Restricted Growth and Volatility Relationships Reexamined: The Role of Aggregation(Southern Illinois University, 2024-05-21) Khan, Haya; Morshed, Akm MahbubAbstract: This dissertation studies the relationship between output growth rate and its volatility. This study sheds light on International, Regional, and Development Economics literature. In the first chapter, we revisit the relationship between output growth rate and its volatility using cross-section techniques for our panel data set from 60 countries from 1970 to 2019. In addition to the conventional volatility measurement of the standard deviation, we incorporate the higher moments, such as skewness and kurtosis, as volatility measures. Higher moments further sharpen our understanding of the volatility and growth rate relationship. We also examine the role of the irreversibility of investment, a purported proximate factor for increased volatility in theory but not applied to empirical models, on the growth rate. We find that a higher level of the irreversibility of investment tends to reduce the growth rate. In the second chapter, we examine the growth-volatility relationship covering manufacturing activities at the two-digit level in 32 countries. In particular, we conduct a comprehensive analysis to reveal the long-term relationship between output growth rate and volatility over 1970 – 2019 within countries and across sectors. We have data for each manufacturing subsector for each country over a long period. We have redefined the growth rate and volatility measures with alternative definitions such as cross-country and cross-sector across time. This offers additional advantages from an econometric perspective, as the large cross-sectional dimension is beneficial when estimating the determinants of growth rate. Moreover, our study assesses the evolution of the long-term relationship between economic sectoral growth rate and sectoral volatility over time. Overall, we find that growth rate and volatility are negatively related, with a few exceptions. The third chapter investigates the relationship between regional growth rate and volatility in U.S. state regions. We use disaggregated data for manufacturing activities over the period 1977 – 2021. We find a significant positive relationship between sectoral volatility and GDP per worker growth rate across the U.S. states regions, meaning that manufacturing volatile sectors for the U.S. are growing faster. This finding is also robust in including additional control variables in the analysis, thus confirming that volatility does not capture the effect of other potential determinants of GDP growth in the manufacturing sectors. We further examine how policy structure and geographical similarity affect regional growth rates, in which we distinguish between the Democrat and Republican Parties and Coastline and Non-Coastline states. We find that the growth rate and volatility relationship has been weaker for Democrat-leading states and geographically more open states (states with a coastline). This suggests that the growth rate and volatility relationship can be altered by having a supporting fiscal policy or having a more open economy.8 0