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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Motivation and Commitment to Activism: A Group Differential Approach to Investigating Motivation and Motivational Change Among Black and Latinx Adolescents Across High School

May, Sidney January 2022 (has links)
Thesis advisor: Scott C. Seider / Engagement in sociopolitical activism, such as protesting, has important implications for youth of color and for the communities in which they live (Ballard & Ozer, 2016; Ginwright, 2010; Hope & Spencer, 2017). Critical Consciousness (CC; Freire, 1970/1998; Watts et al., 2011) and Youth Sociopolitical Development Theory (Youth SPD; Watts & Flanagan, 2007) are two prominent frameworks for investigating sociopolitical activism among youth of color. Although both frameworks position motivation as one of the key factors influencing youth activism, motivation is narrowly defined as a single construct—one’s sense of efficacy to effect change. Using motivation constructs from two established motivation frameworks, Self-Determination Theory (SDT; Deci & Ryan, 2008; Ryan & Deci, 2000) and Regulatory Focus Theory (RFT; Higgins, 1997), this dissertation investigated the multidimensional nature of motivation in relation to Black and Latinx adolescents’ commitment to activism. Drawing from a longitudinal data set examining Black and Latinx adolescents’ civic development over four years of high school (N = 733), I used group differential approaches (latent profile analysis, latent profile transition analysis, and latent profile moderation) to (a) identify distinct combinations of motivations among Black and Latinx high school students in ninth, tenth, and twelfth grade, (b) assess whether and the extent to which adolescents changed profile membership across high school, (c) examine motivation profiles in tenth grade as predictors of commitment to activism in twelfth grade, and (d) examine motivation profiles in tenth grade as moderators of the relation between adolescents’ analysis of social problems in tenth grade and their commitment to activism addressing these problems in twelfth grade (controlling for their initial commitment to activism). I identified two motivation profiles in ninth grade, four motivation profiles in tenth grade, and four motivation profiles in twelfth grade. At both tenth and twelfth grade, I named the motivation profiles: “Low Motivation,” “High Motivation,” “Moderate Motivation, Low Autonomy,” and “Moderate Motivation, High Autonomy.” At both time points, the “Low Motivation” profile comprised the smallest proportion of the sample and the “Moderate Motivation, High Autonomy” profile comprised the largest proportion of the sample. Most youth shifted to a different motivation profile over time. Adolescents in the “High Motivation” profile at the end of tenth grade reported the highest average commitment to activism at the end of twelfth grade; however, this number was only statistically significantly higher than the “Moderate Motivation, Low Autonomy” profile. Contrary to expectations, youths’ social analysis in tenth grade was not predictive of their commitment to activism in twelfth grade; thus, there was no latent profile moderation in relation to social analysis and commitment to activism. Instead, I did find evidence that motivation profile membership moderated the relation between commitment to activism at the end of tenth grade on commitment to activism at the end of twelfth grade. Overall, results suggest that adolescents’ motivation is multidimensional and incredibly dynamic. Future CC/Youth SPD research should consider investigating a more complete set of established motivation constructs in relation to youths’ sociopolitical development. / Thesis (PhD) — Boston College, 2022. / Submitted to: Boston College. Lynch School of Education. / Discipline: Counseling, Developmental and Educational Psychology.
122

Review of Methods for Calculating Pressure Profiles of Explosive Air Blast and its Sample Application

Chock, Jeffrey Mun Kong 04 May 1999 (has links)
Blast profiles and two primary methods of determining them were reviewed for use in the creation of a computer program for calculating blast pressures which serves as a design tool to aid engineers or analysts in the study of structures subjected to explosive air blast. These methods were integrated into a computer program, BLAST.F, to generate air blast pressure profiles by one of these two differing methods. These two methods were compared after the creation of the program and can conservatively model the effects of spherical air blast and hemispherical surface burst. The code, BLAST.F, was used in conjunction with a commercial finite element code (NASTRAN) in a demonstration of method on a 30 by 30 inch aluminum 2519 quarter plate of fixed boundary conditions in hemispherical ground burst and showed good convergence with 256 elements for deflection and good agreement in equivalent stresses of a point near the blast between the 256 and 1024 element examples. Application of blasts to a hypothetical wing comprised of aluminum 7075-T6 was also conducted showing good versatility of method for using this program with other finite element models. / Master of Science
123

Tree Profile Equations for Black Walnut (Juglans nigra L.) and Green Ash (Fraxinus Pennsylvanica) in Mississippi

Beard, Jacob R 17 August 2013 (has links)
Black walnut (Juglans nigra L.) is a valued, Mississippi tree species with very little published mensurational data. Tree profile equations are effective tree volume predictors but are typically developed from measurements on destructively sampled trees, an impractical method on valuable species. This study developed black walnut and green ash (Fraxinus pennsylvanica) profile equations from non-destructive measurements using a Barr & Stroud FP15 optical dendrometer. Accuracy of the dendrometer was validated by taking both optical dendrometer and felled, direct measurements on green ash trees. Two profile models were evaluated for measured tree data. Separate equations were created from optical dendrometer tree profile data for black walnut and green ash and felled tree profile data for green ash. The Barr & Stroud allowed tree profile equations to be developed from standing tree measurements with acceptable accuracy, thus providing useful tools towards the valuation and management of southeastern black walnut and green ash.
124

Optical and Photovoltaic Properties of Copper Indium-Gallium Diselenide Materials and Solar Cells

Aryal, Puruswottam 19 December 2014 (has links)
No description available.
125

Physico-Chemical, Minearlogical and Micromorphological Studies on Alfisol and Spodosol Profiles from Southern Ontario, Canada

Hathout, Salah 05 1900 (has links)
The relationship between soil properties and micromorphological features was studied in six Alfisol and six Spodosol profiles from Southern Ontario. The total porosity of the soil material was largely related to the size, shape and conformation of the soil voids in thin sections, while the differential development of plasma fabric could be used to discern a sequence of degrees of weathering which was also expressed by various mineralogical and physico-chemical indices. The relative proportions of soil constituents in thin sections was successfully used to indicate the existing textural discontinuities in five of the profiles studied. The elementary structure of soil thin sections is considered the most important micromorphological feature in the investigation of the degree of B horizon development in both Alfisol and Spodosol profiles. / Thesis / Doctor of Philosophy (PhD)
126

Effectiveness of operational profile-based testing

Zhakipbayev, Olzhas, Bekey, Aisulu January 2021 (has links)
The operational profile-based testing is currently not a well-studied topic and there are no specific instructions for writing test cases for testing the program. In our thesis, we presented our idea about on the basis of what data test cases can be written. Also, in order to show the effectiveness of operational profile-based testing, we additionally described the equivalent partitioning testing technique. The software for this experiment was taken from the open-source SIR repository. We have selected software: “Account”, that was tested by two different testing methods. The test results of both techniques were compared and it was determined that the operational profile-based testing technique is more effective.
127

The impact of substance abuse among youth on the risk profile of Bekkersdal community / Mabeba Gladys Kekana

Kekana, Mabeba Gladys January 2015 (has links)
The influx of youth abusing substances is a major problem. The effect of substance abuse may have far-reaching consequences for defining the vulnerability of the offending group as well as for contributing to the disaster risk faced by the community as a whole. The effects of substance abuse on young people have the potential to contribute to an increased vulnerability of this group. It becomes the responsibility of the family and community to bear the burden of its drug-afflicted members and the implications of their addiction. The study was conducted in Bekkersdal, which is a community that has a significant problem with youth abusing substances. The degree to which their abuse affects families and the broader community in terms of increasing risk has not been examined. The dissertation aims to evaluate the effect of substance abuse among the youth on the risk profile of the Bekkersdal community. According to Disaster Risk Reduction, one of the important activities of the state is to increase capacity of communities and households to minimize the risk that may occur and also most importantly, monitoring the likelihood of and the state of alertness to disasters that may occur. A qualitative, explorative research design was employed and data gathered using structured interviews involving 30 adults namely School Principals, Teachers, Community Social workers, Community Leaders, Religious Leaders, Disaster managers and a Nurse from the area. The interviews were analysed by means of themes. The research indicated that substance-abusing youth create conditions which undermine human, physical and social capital and hence contribute to instability in the livelihood-based system. It was also evident to this research that it encourages the importance of engaging community members in discussions about aspects that concern them which is an empowerment process in itself. As they become more involved, they also have hope that things will work better for them by actively rebuilding their own lives and communities. All the information gathered revealed the link between the negative impacts of substance abuse and its risk profile in the Bekkersdal community. / M Development and Management, North-West University, Potchefstroom Campus, 2015
128

Neutronic simulation of a European Pressurised Reactor / Ontlametse Emmanuel Montwedi

Montwedi, Ontlametse Emmanuel January 2014 (has links)
The South African government’s integrated resource plan for electricity IRP2010 states that the country plans to have an additional 9.6 GW of nuclear power on the national electricity grid by 2030. In support of this, the NRF-funded SARChI Research Chair in Nuclear Engineering within the School of Mechanical and Nuclear Engineering at the North-West University recently initiated research studies focused on Light Water Reactor (LWR) systems. These studies inter alia involve coupled neutronic and thermal hydraulic analyses of selected LWR systems. This study focuses on the steady state neutronic analysis of the European Pressurised Reactor (EPR) using Monte-Carlo N-Particle (MCNP5). The neutronic model will in due course be coupled to a thermal hydraulic model forming part of a broader study of the system. The Monte Carlo neutron transport code MCNP5 has been widely used since the 1950s for analysis of existing and future reactor systems due to its ability to simulate complex fuel assemblies without making any significant approximations. The primary aim of the study was to develop an input model for a representative fresh fuel assembly of the US EPR reactor core from which the fluxes and fission power of the reactor can be obtained. There after a 3D model of full EPR core developed by the school of mechanical and nuclear engineering based on findings of this work is also tested. The results are compared to those in the US EPR Final Safety Analysis Report. Agreement in major core operational parameters including the keff eigenvalue, axial and radial power profiles and control rod worth are evaluated, from which consistency of the model and results will be confirmed. Further convergence of the model within a reasonable time is assessed. / MSc (Engineering Sciences in Nuclear Engineering), North-West University, Potchefstroom Campus, 2014
129

The impact of substance abuse among youth on the risk profile of Bekkersdal community / Mabeba Gladys Kekana

Kekana, Mabeba Gladys January 2015 (has links)
The influx of youth abusing substances is a major problem. The effect of substance abuse may have far-reaching consequences for defining the vulnerability of the offending group as well as for contributing to the disaster risk faced by the community as a whole. The effects of substance abuse on young people have the potential to contribute to an increased vulnerability of this group. It becomes the responsibility of the family and community to bear the burden of its drug-afflicted members and the implications of their addiction. The study was conducted in Bekkersdal, which is a community that has a significant problem with youth abusing substances. The degree to which their abuse affects families and the broader community in terms of increasing risk has not been examined. The dissertation aims to evaluate the effect of substance abuse among the youth on the risk profile of the Bekkersdal community. According to Disaster Risk Reduction, one of the important activities of the state is to increase capacity of communities and households to minimize the risk that may occur and also most importantly, monitoring the likelihood of and the state of alertness to disasters that may occur. A qualitative, explorative research design was employed and data gathered using structured interviews involving 30 adults namely School Principals, Teachers, Community Social workers, Community Leaders, Religious Leaders, Disaster managers and a Nurse from the area. The interviews were analysed by means of themes. The research indicated that substance-abusing youth create conditions which undermine human, physical and social capital and hence contribute to instability in the livelihood-based system. It was also evident to this research that it encourages the importance of engaging community members in discussions about aspects that concern them which is an empowerment process in itself. As they become more involved, they also have hope that things will work better for them by actively rebuilding their own lives and communities. All the information gathered revealed the link between the negative impacts of substance abuse and its risk profile in the Bekkersdal community. / M Development and Management, North-West University, Potchefstroom Campus, 2015
130

Neutronic simulation of a European Pressurised Reactor / Ontlametse Emmanuel Montwedi

Montwedi, Ontlametse Emmanuel January 2014 (has links)
The South African government’s integrated resource plan for electricity IRP2010 states that the country plans to have an additional 9.6 GW of nuclear power on the national electricity grid by 2030. In support of this, the NRF-funded SARChI Research Chair in Nuclear Engineering within the School of Mechanical and Nuclear Engineering at the North-West University recently initiated research studies focused on Light Water Reactor (LWR) systems. These studies inter alia involve coupled neutronic and thermal hydraulic analyses of selected LWR systems. This study focuses on the steady state neutronic analysis of the European Pressurised Reactor (EPR) using Monte-Carlo N-Particle (MCNP5). The neutronic model will in due course be coupled to a thermal hydraulic model forming part of a broader study of the system. The Monte Carlo neutron transport code MCNP5 has been widely used since the 1950s for analysis of existing and future reactor systems due to its ability to simulate complex fuel assemblies without making any significant approximations. The primary aim of the study was to develop an input model for a representative fresh fuel assembly of the US EPR reactor core from which the fluxes and fission power of the reactor can be obtained. There after a 3D model of full EPR core developed by the school of mechanical and nuclear engineering based on findings of this work is also tested. The results are compared to those in the US EPR Final Safety Analysis Report. Agreement in major core operational parameters including the keff eigenvalue, axial and radial power profiles and control rod worth are evaluated, from which consistency of the model and results will be confirmed. Further convergence of the model within a reasonable time is assessed. / MSc (Engineering Sciences in Nuclear Engineering), North-West University, Potchefstroom Campus, 2014

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