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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.
31

Scanning tunnelling microscopy studies of liquid crystals

Rivera-Hernandez, Margarita January 1997 (has links)
No description available.
32

Analysing educational transitions in upper secondary and higher education in Mexico : an empirical application of the capability approach and sociological perspectives on inequalities in education

Mendoza Cazarez, Dulce Carolina January 2017 (has links)
In spite of educational expansion, a considerable number of individuals are not able to participate in upper secondary and higher education in Mexico. The main purpose of this thesis is to examine the factors influencing individuals’ opportunities to make higher educational transitions in Mexico. These transitions are: participation in upper secondary education, completion of upper secondary education and progression to higher education. A parallel objective is to investigate the predictors of persons’ institutional location in the upper secondary level. It is argued that the majority of the international studies in the field of educational transitions, as well as most of the studies conducted for Mexico in this area, have focused on examining the chances of entering an educational level but less attention has been paid on examining the opportunities of concluding a given level of education. This dissertation explores the chances of completing upper secondary education and it incorporates school dropouts in the analysis of educational transitions. Another important purpose is to conduct interdisciplinary theoretical work. A theoretical framework composed of the capability approach, sociocultural reproduction theory and contemporary sociological perspectives on inequalities in education is used to operationalize key concepts and to provide possible explanations of persons’ decisions to participate in upper secondary and higher education. From the capability approach, human agency, preferences and rationality have influence on educational decision-making. From Bourdieu’s sociocultural reproduction theory, educational choices are not freely made because they are determined by cultural and socioeconomic constraints. Furthermore, drawing on the integrative theoretical framework several hypotheses are formulated and some of them are empirically tested using national survey data for Mexico: The School Dropouts Survey, 2011. The investigation adopts a quantitative methodology which includes the estimation of binomial and multinomial logistic regression models. This study found that the effects of ascriptive factors such as social and ethnic background, gender and geographical location vary for each school transition. In addition, some of these factors contribute to predict person’s location in academic and vocational pathways of upper secondary education. Nevertheless, individuals’ capacity to attain higher levels of schooling is not completely determined by structural-related aspects. This thesis found that agency and capability dimensions such as freedom to choose school, aspirations and persons’ preferences towards education are not only intrinsically valuable but instrumentally relevant for making higher educational transitions. Furthermore, the type of institution attended and academic performance matter for entering and completing upper secondary and for attending higher education. This thesis concludes that the degree to which structural factors, agency and capability dimensions and school experiences make an impact on individuals’ educational trajectories is significantly affected by specific institutional arrangements at each stage of education. Finally, the empirical evidence of this thesis has a number of important implications for educational policies in Mexico.
33

Numerical studies of a generalized double exchange model =: 廣義雙交換模型的數值硏究. / 廣義雙交換模型的數值硏究 / Numerical studies of a generalized double exchange model =: Guang yi shuang jiao huan mo xing de shu zhi yan jiu. / Guang yi shuang jiao huan mo xing de shu zhi yan jiu

January 1999 (has links)
Wong Chung Ki. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 93-94). / Text in English; abstracts in English and Chinese. / Wong Chung Ki. / Abstract --- p.i / Acknowledgement --- p.iii / Contents --- p.iv / List of Figures --- p.viii / List of Tables --- p.xii / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Motivation --- p.1 / Chapter 1.2 --- Double exchange model --- p.3 / Chapter 1.3 --- This project --- p.5 / Chapter Chapter 2. --- The generalized double exchange model --- p.6 / Chapter 2.1 --- Assumptions of the model --- p.6 / Chapter 2.2 --- Transfer process of the mobile electrons --- p.7 / Chapter 2.3 --- Double exchange model --- p.9 / Chapter 2.4 --- The generalized double exchange model --- p.10 / Chapter 2.5 --- Previous results on the model --- p.13 / Chapter 2.5.1 --- Solution for two localized spins --- p.13 / Chapter 2.5.2 --- Ground state configuration for one doping electron and the electron concentration at half fill --- p.13 / Chapter 2.5.3 --- The planar spiral state and the canted ferromagnetic state --- p.14 / Chapter Chapter 3. --- Ground state calculations --- p.16 / Chapter 3.1 --- Minimization of ground state energy --- p.17 / Chapter 3.2 --- Energy and spin configuration --- p.18 / Chapter 3.3 --- Occupation number of mobile electrons --- p.19 / Chapter 3.4 --- Rotated occupation number of mobile electrons --- p.19 / Chapter Chapter 4. --- One-dimensional ground state results --- p.21 / Chapter 4.1 --- Zero superexchange coupling --- p.21 / Chapter 4.1.1 --- Total energy of the system --- p.21 / Chapter 4.1.2 --- Spin configuration and nearest neighbor spin-spin correlation --- p.23 / Chapter 4.1.3 --- Occupation number --- p.29 / Chapter 4.2 --- Antiferromagnetic superexchange coupling --- p.34 / Chapter 4.2.1 --- Total energy of the system --- p.35 / Chapter 4.2.2 --- Spin configuration and nearest neighbor spin-spin correlation --- p.36 / Chapter 4.2.3 --- Occupation number --- p.39 / Chapter 4.3 --- Discussions on the one-dimensional results --- p.43 / Chapter Chapter 5. --- Two-dimensional ground state results --- p.46 / Chapter 5.1 --- Zero superexchange coupling --- p.46 / Chapter 5.1.1 --- Total energy of the system --- p.46 / Chapter 5.1.2 --- Localized spin configuration --- p.47 / Chapter 5.1.3 --- Occupation number --- p.51 / Chapter 5.2 --- Nonzero superexchange coupling --- p.54 / Chapter 5.2.1 --- Total energy of the system --- p.54 / Chapter 5.2.2 --- Spin configuration --- p.54 / Chapter 5.2.3 --- Occupation number --- p.57 / Chapter 5.3 --- Discussions --- p.59 / Chapter Chapter 6. --- Finite temperature calculations on the model --- p.62 / Chapter 6.1 --- Quantum Monte Carlo simulation --- p.62 / Chapter 6.2 --- Heat capacity and magnetic susceptibility --- p.63 / Chapter 6.3 --- Localized spin-spin correlation --- p.64 / Chapter Chapter 7. --- Results at finite temperature --- p.65 / Chapter 7.1 --- Two-dimensional results without superexchange interaction --- p.65 / Chapter 7.1.1 --- Fourier transform of the spin-spin correlation --- p.65 / Chapter 7.1.2 --- Occupation number --- p.68 / Chapter 7.2 --- Two-dimensional results with nonzero superexchange interaction --- p.73 / Chapter 7.2.1 --- Fourier transform of the spin-spin correlation --- p.73 / Chapter 7.2.2 --- Occupation number --- p.74 / Chapter 7.3 --- Three-dimensional results with anisotropic exchange interaction --- p.77 / Chapter 7.3.1 --- Fourier transform of the spin-spin correlation --- p.77 / Chapter 7.3.2 --- Occupation number --- p.79 / Chapter 7.3.3 --- Magnetization --- p.81 / Chapter 7.3.4 --- Heat capacity --- p.81 / Chapter 7.3.5 --- Magnetic susceptibility --- p.82 / Chapter 7.3.6 --- Discussions --- p.83 / Chapter Chapter 8. --- Conclusions --- p.85 / Chapter Appendix A. --- Details on Euler rotation of the localized spin --- p.87 / Chapter Appendix B. --- Details on the calculation of the occupation number --- p.89 / Chapter B.1 --- Occupation number --- p.89 / Chapter B.2 --- Rotated occupation number --- p.90 / Chapter Appendix C. --- Fourier transform of the spin-spin correlation at T≠0 --- p.92 / Bibliography
34

Phases and Phase Transitions in Quantum Ferromagnets

Sang, Yan 14 January 2015 (has links)
In this dissertation we study the phases and phase transition properties of quantum ferromagnets and related magnetic materials. We first investigate the effects of an external magnetic field on the Goldstone mode of a helical magnet, such as MnSi. The field introduces a qualitatively new term into the dispersion relation of the Goldstone mode, which in turn changes the temperature dependences of the contributions of the Goldstone mode to thermodynamic and transport properties. We then study how the phase transition properties of quantum ferromagnets evolve with increasing quenched disorder. We find that there are three distinct regimes for different amounts of disorder. When the disorder is small enough, the quantum ferromagnetic phase transitions is generically of first order. If the disorder is in an intermediate region, the ferromagnetic phase transition is of second order and effectively characterized by mean-field critical exponents. If the disorder is strong enough the ferromagnetic phase transitions are continuous and are characterized by non-mean-field critical exponents.
35

Rural routes : a study of rural high school graduate life transitions

Gress, Lorraine Helen 22 September 2009
This phenomenological retrospective study investigates the transitional experiences of five graduates from one rural schools classes. The study has two guiding themes: (a) the factors which influence graduating students decisions for their futures, and (b) the transitions they experience following those decisions.<p> High school graduation and the subsequent transition to life after high school was the phenomenon that each participant had undergone. During semi-structured interviews, participants discussed their decisions before and after that delineating moment. The research question was: What supports do recent graduates perceive to have existed in a small rural school to assist students in their transition from school to post secondary education or the workforce? Follow up interview questions were: (a) What challenges have recent graduates faced as they transitioned from high school to their current positions as post secondary students or employees? (b) What supports do recent graduates believe should be implemented to assist future graduates in their upcoming transitions from high school to post secondary education or the workforce?<p> The study results indicated that graduates perceive schools role as peripheral or tangential to their transition to their post secondary lives. The caring and interested relationships developed between students and school personnel while important, are at best, incidental and not perceived to be instrumental and in one case may be seen as limiting. The data reveals the significant influence of family, or social habitus and cultural capital on both the career and life decisions and on the transitions experienced by the participants as they adjusted to life after high school. Challenges and transitions were recounted and participant suggestions for schools were discussed. I indicated the need for increased professional development for teachers in the area of career development and transitioning, as well as the need for an expanded recognition of the pivotal roles held by family members in the transition to adulthood. Finally, I reflected on areas for further investigation which include gathering more insights from young adults and students as well as their families, investigating the transitions implicit in entering the workforce, and exploring the issue of providing hope for rural communities and schools.
36

Becoming a Family Physician – Exploring the Experiences of Residents During the First Six Months of PostgraduateTraining

Martin, Dawn 08 February 2011 (has links)
Becoming a Family Physician – Exploring the Experiences of Residents During the First Six Months of Postgraduate Training describes the early training experience of residents from their perspective as they begin a postgraduate program in Family Medicine. A case study approach using focus groups and individual interviews was used to gain insight into the resident-participant’s experiences of the first six months of training. Resident-participants were asked to describe their concerns, changes that occurred and the influences they attributed to those changes as a way to explore their early training experiences from their perspective. This study found resident-trainees do not begin a Family Medicine postgraduate training program knowing what it means to be a Family Physician, but must learn what it means to fulfill this role. From the participants’ perspective, this process involves adjusting to significant shifts in responsibility in the areas of Knowledge, Practice Management and Relationships that occur when they make the transition from being medical students in undergraduate training to doctors responsible for the outcome of care during postgraduate training. As the participants began postgraduate training they were eager to accept the responsibility of being the doctor, but were uncertain they had the necessary medical experience and expertise for someone calling themselves the doctor. The experience of practice, which included developing relationships with different patients over time (continuity of care) was particularly influential in helping the participants gain confidence in fulfilling the role of doctor and learning that the role of Family Physician is complex, multifaceted and not limited to their initial concept of doctoring. As the participants adjusted to their new responsibilities, they gained confidence in their new role as doctor, which subsequently led to a more comprehensive understanding of what it meant to be a Family Physician. This study was able to contribute to what little is know about the transition into a postgraduate Family Medicine program by illuminating from the resident-participant’s perspective how the transition is experienced. In doing so, medical educators have a better understanding of the early training experience of resident-trainees and how these experiences contribute to consolidating their new professional identity.
37

Becoming a Family Physician – Exploring the Experiences of Residents During the First Six Months of PostgraduateTraining

Martin, Dawn 08 February 2011 (has links)
Becoming a Family Physician – Exploring the Experiences of Residents During the First Six Months of Postgraduate Training describes the early training experience of residents from their perspective as they begin a postgraduate program in Family Medicine. A case study approach using focus groups and individual interviews was used to gain insight into the resident-participant’s experiences of the first six months of training. Resident-participants were asked to describe their concerns, changes that occurred and the influences they attributed to those changes as a way to explore their early training experiences from their perspective. This study found resident-trainees do not begin a Family Medicine postgraduate training program knowing what it means to be a Family Physician, but must learn what it means to fulfill this role. From the participants’ perspective, this process involves adjusting to significant shifts in responsibility in the areas of Knowledge, Practice Management and Relationships that occur when they make the transition from being medical students in undergraduate training to doctors responsible for the outcome of care during postgraduate training. As the participants began postgraduate training they were eager to accept the responsibility of being the doctor, but were uncertain they had the necessary medical experience and expertise for someone calling themselves the doctor. The experience of practice, which included developing relationships with different patients over time (continuity of care) was particularly influential in helping the participants gain confidence in fulfilling the role of doctor and learning that the role of Family Physician is complex, multifaceted and not limited to their initial concept of doctoring. As the participants adjusted to their new responsibilities, they gained confidence in their new role as doctor, which subsequently led to a more comprehensive understanding of what it meant to be a Family Physician. This study was able to contribute to what little is know about the transition into a postgraduate Family Medicine program by illuminating from the resident-participant’s perspective how the transition is experienced. In doing so, medical educators have a better understanding of the early training experience of resident-trainees and how these experiences contribute to consolidating their new professional identity.
38

Rural routes : a study of rural high school graduate life transitions

Gress, Lorraine Helen 22 September 2009 (has links)
This phenomenological retrospective study investigates the transitional experiences of five graduates from one rural schools classes. The study has two guiding themes: (a) the factors which influence graduating students decisions for their futures, and (b) the transitions they experience following those decisions.<p> High school graduation and the subsequent transition to life after high school was the phenomenon that each participant had undergone. During semi-structured interviews, participants discussed their decisions before and after that delineating moment. The research question was: What supports do recent graduates perceive to have existed in a small rural school to assist students in their transition from school to post secondary education or the workforce? Follow up interview questions were: (a) What challenges have recent graduates faced as they transitioned from high school to their current positions as post secondary students or employees? (b) What supports do recent graduates believe should be implemented to assist future graduates in their upcoming transitions from high school to post secondary education or the workforce?<p> The study results indicated that graduates perceive schools role as peripheral or tangential to their transition to their post secondary lives. The caring and interested relationships developed between students and school personnel while important, are at best, incidental and not perceived to be instrumental and in one case may be seen as limiting. The data reveals the significant influence of family, or social habitus and cultural capital on both the career and life decisions and on the transitions experienced by the participants as they adjusted to life after high school. Challenges and transitions were recounted and participant suggestions for schools were discussed. I indicated the need for increased professional development for teachers in the area of career development and transitioning, as well as the need for an expanded recognition of the pivotal roles held by family members in the transition to adulthood. Finally, I reflected on areas for further investigation which include gathering more insights from young adults and students as well as their families, investigating the transitions implicit in entering the workforce, and exploring the issue of providing hope for rural communities and schools.
39

Synchronization of the extended Kuramoto model

Lin, Huang-jyun 26 June 2009 (has links)
none
40

Application of generalized Hamiltonian dynamics to modified Coulomb potential

Camarena, Julian Antolin. Oks, E. A. January 2008 (has links) (PDF)
Thesis (M.S.)--Auburn University, 2008. / Abstract. Includes bibliographical references (p. 29-30).

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