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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.
101

Geometric phase in quantum mechanics =: 量子力學之幾何相位. / 量子力學之幾何相位 / Geometric phase in quantum mechanics =: Liang zi li xue zhi ji he xiang wei. / Liang zi li xue zhi ji he xiang wei

January 2002 (has links)
Fung Ho Tak. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 107-110). / Text in English; abstracts in English and Chinese. / Fung Ho Tak. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Introduction to Geometric phase --- p.1 / Chapter 1.2 --- Introduction to Bose Einstein Condensation --- p.3 / Chapter 1.3 --- Motivation --- p.4 / Chapter 2 --- Review on Geometric phase --- p.6 / Chapter 2.1 --- Geometric phase achieved by undergoing adiabatic cyclic evolution --- p.7 / Chapter 2.2 --- Geometric phase acquired by undergoing cyclic evolution --- p.10 / Chapter 2.3 --- Geometric phase acquired by undergoing any evolution --- p.13 / Chapter 2.4 --- Geometrical representation of a two-level system --- p.15 / Chapter 3 --- Geometric Phase in Physical Systems --- p.17 / Chapter 3.1 --- Aharonov-Bohm Effect --- p.18 / Chapter 3.2 --- An Electron in a Magnetic Field --- p.20 / Chapter 3.2.1 --- The geometric phase β0(t) --- p.23 / Chapter 3.2.2 --- The geometric phase β1(t) --- p.28 / Chapter 3.3 --- Geometrical picture of the two-level quantum system --- p.32 / Chapter 3.3.1 --- Geometrical interpretation of β0(t) --- p.33 / Chapter 3.3.2 --- Geometrical interpretation of β1(t) --- p.36 / Chapter 3.4 --- Summary --- p.37 / Chapter 4 --- Geometric phase of a particle in a vibrating cavity --- p.39 / Chapter 4.1 --- Energy of a particle in a vibrating spherical cavity --- p.40 / Chapter 4.2 --- Geometric phase of a particle in a vibrating spherical cavity --- p.43 / Chapter 4.2.1 --- β0(t) of a particle in a vibrating cavity --- p.44 / Chapter 4.2.2 --- β1(t) of a particle in a vibrating cavity --- p.46 / Chapter 4.3 --- The Rotating-Wave Approximation approach --- p.46 / Chapter 4.3.1 --- Energy of the particle by using RWA --- p.49 / Chapter 4.3.2 --- Geometric phase of the particle by RWA --- p.50 / Chapter 4.4 --- The SU(2) Method --- p.52 / Chapter 4.5 --- Summary --- p.53 / Chapter 5 --- Review on Bose Einstein Condensation --- p.55 / Chapter 6 --- Energies and wavefunctions of a condensate --- p.63 / Chapter 6.1 --- perturbation approach to solve the nonlinear Schrodinger equation --- p.63 / Chapter 6.2 --- Energy of a BEC in an oscillating harmonic trap --- p.66 / Chapter 6.3 --- Wavefunction of the condensate in a vibrating harmonic trap --- p.72 / Chapter 6.4 --- Energies and wavefunctions of SHO --- p.76 / Chapter 6.5 --- Summary --- p.78 / Chapter 7 --- "(δr)2,(δpr)2 and geometric phase of a condensate" --- p.79 / Chapter 7.1 --- Uncertainties in position and momentum --- p.80 / Chapter 7.1.1 --- (δr)2 and (δpr)2 for a BEC in an oscillating trap --- p.80 / Chapter 7.1.2 --- (δr) and (δpr) in a oscillating SHO --- p.85 / Chapter 7.2 --- Geometric phase of BEC --- p.85 / Chapter 7.2.1 --- β0(t) of BEC --- p.87 / Chapter 7.2.2 --- β1(t)of BEC --- p.90 / Chapter 7.3 --- Summary --- p.92 / Chapter 8 --- Summary --- p.95 / Chapter A --- Parameter space and Berry's phase for degenerate Hamilto- nian --- p.99 / Chapter B --- Dirac Phase Factor --- p.101 / Chapter C --- Hamiltonian of a frequency-varying harmonics oscillator --- p.104 / Bibliography --- p.107
102

On the performance bound of turbo code.

January 1999 (has links)
by Ng Siu Wah. / Thesis submitted in: August 1998. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 49-[52]). / Abstract also in Chinese. / Chapter 1 --- Introduction and motivations --- p.1 / Chapter 1.1 --- Overview of Coding Technology --- p.2 / Chapter 1.2 --- Recent Breakthrough - Turbo Code --- p.3 / Chapter 1.3 --- Organization of the Thesis --- p.4 / Chapter 2 --- Basics of Turbo Codes --- p.5 / Chapter 2.1 --- A Brief Introduction of Turbo Codes --- p.6 / Chapter 2.1.1 --- Constituent Encoders with interleaver --- p.6 / Chapter 2.1.2 --- Iterative Decoder --- p.8 / Chapter 2.2 --- Additional remarks on Turbo Codes --- p.12 / Chapter 2.2.1 --- RSC encoders --- p.12 / Chapter 2.2.2 --- Interleaver --- p.14 / Chapter 2.3 --- Performance Evaluation of Turbo Codes --- p.15 / Chapter 2.3.1 --- Union Bound --- p.15 / Chapter 2.3.2 --- Weight Enumerating Function --- p.16 / Chapter 2.3.3 --- Uniform Interleaver --- p.17 / Chapter 3 --- An Improved Performance Bound for Turbo Codes --- p.20 / Chapter 3.1 --- Motivations --- p.21 / Chapter 3.2 --- Duman-Salehi's bound for Turbo Code --- p.22 / Chapter 3.2.1 --- Notations and definitions --- p.22 / Chapter 3.2.2 --- Word Error Probability --- p.23 / Chapter 3.3 --- Improved bounds for Turbo Code --- p.26 / Chapter 3.3.1 --- Preliminaries --- p.26 / Chapter 3.3.2 --- Generalization of Duman-Salehi's Bounds --- p.28 / Chapter 3.3.3 --- An Improved Bound on Word Error Probability --- p.30 / Chapter 3.3.4 --- An Improved Bound on Bit Error Probability --- p.34 / Chapter 3.4 --- Results and Discussions --- p.37 / Chapter 3.4.1 --- Assumptions --- p.37 / Chapter 3.4.2 --- Numerical results --- p.37 / Chapter 3.4.3 --- Distance spectra --- p.40 / Chapter 4 --- Concluding Remarks --- p.48 / Bibliography --- p.49
103

Consumer theory

Lanier, Joshua January 2018 (has links)
This thesis consists of three self-contained chapters covering topics in consumer theory. The first chapter presents an estimator for a Marshallian demand function which not only obeys all of the standard assumptions of consumer theory but will also converge to any true demand function which also obeys these standard assumptions. The second chapter explores Giffen behavior in the context of financial assets. The chapter finds that an agent with Maxmin preferences almost always displays Giffen behavior in some financial environments. Giffen behavior is also characterized for other classes of preferences. The last chapter, coauthored with one of my supervisors: John K.-H. Quah, develops a revealed preference test for weakly separable preferences in the spirit of Sydney Afriat. Unlike previous tests, ours does not impose concavity and applies to nonlinear budgets.
104

On thickness of knots and its properties. / On thickness of knots & its properties

January 2006 (has links)
Ho Wing Yin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 67-68). / Abstracts in English and Chinese. / Chapter 0 --- Introduction --- p.5 / Chapter 1 --- Basics of Differential Topology and Knot Theory --- p.7 / Chapter 1.1 --- Elementary Differential Topology --- p.7 / Chapter 1.2 --- Elementary Knot Theory --- p.13 / Chapter 1.2.1 --- Basic Definition --- p.13 / Chapter 1.2.2 --- Regular Projection --- p.14 / Chapter 1.2.3 --- Classical Knot Invariants --- p.15 / Chapter 2 --- Thickness of Knots --- p.17 / Chapter 2.1 --- Thickness and its Curvature --- p.17 / Chapter 2.2 --- Consequences of the Main Theorem --- p.27 / Chapter 2.3 --- Polygonal Representation of Knot --- p.30 / Chapter 2.4 --- Self-distance and Main Theorem --- p.35 / Chapter 3 --- Energy --- p.37 / Chapter 3.1 --- Normal Energy and Symmetric Energy --- p.37 / Chapter 3.2 --- Mobius Energy --- p.48 / Chapter 3.3 --- Another Formulation of Mobius Energy --- p.57 / Chapter 3.4 --- A Non Self-Repulsive Energy Function --- p.62 / Bibliography --- p.67
105

Quantum entanglement in the S=1/2 spin ladder with ring exchange. / 帶有環交換作用的自旋1/2梯子模型中的量子纠缠 / Quantum entanglement in the S=1/2 spin ladder with ring exchange. / Dai you huan jiao huan zuo yong de zi xuan 1/2 ti zi mo xing zhong de liang zi jiu chan

January 2006 (has links)
Song Junliang = 帶有環交換作用的自旋1/2梯子模型中的量子纠缠 / 宋均亮. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 60-67). / Text in English; abstracts in English and Chinese. / Song Junliang = Dai you huan jiao huan zuo yong de zi xuan 1/2 ti zi mo xing zhong de liang zi jiu chan / Song Junliang. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- What is Entanglement --- p.1 / Chapter 1.2 --- Quantum Information and Entanglement --- p.4 / Chapter 1.3 --- Entanglement in Condensed Matter Physics --- p.6 / Chapter 1.4 --- The S = 1/2 Spin Ladder with Ring Exchange --- p.9 / Chapter 1.5 --- Arrangement of the Thesis Writing --- p.11 / Chapter 2 --- Measures of Entanglement --- p.13 / Chapter 2.1 --- Axiomatic Approach --- p.14 / Chapter 2.2 --- Entropy of entanglement in pure states --- p.16 / Chapter 2.3 --- Concurrence --- p.17 / Chapter 2.4 --- Negativity --- p.19 / Chapter 2.5 --- Other measurements --- p.20 / Chapter 3 --- Entanglement in S=l/2 Ladder with Ring Exchange at T=0 --- p.22 / Chapter 3.1 --- Model Hamiltonian and Phase Diagram --- p.22 / Chapter 3.2 --- Ground-state concurrence --- p.24 / Chapter 3.3 --- Two-site entanglement of the rung and the SU(4) point --- p.29 / Chapter 3.4 --- Scaling behavior of the block-block entanglement --- p.34 / Chapter 3.5 --- Entanglement of the Ferromagnetic state --- p.37 / Chapter 3.6 --- Other Measurements --- p.42 / Chapter 3.7 --- Summary and Discussion --- p.43 / Chapter 4 --- Thermal Entanglement --- p.45 / Chapter 4.1 --- A Four-Spin Plaquette --- p.46 / Chapter 4.2 --- Thermal concurrence --- p.50 / Chapter 4.3 --- Magnetic susceptibility as Entanglement Witness --- p.52 / Chapter 4.4 --- Numerical results in a 6 x 2 ladder --- p.54 / Chapter 4.5 --- Summary and Discussion --- p.55 / Chapter 5 --- Conclusion and future work --- p.58 / Bibliography --- p.60
106

Quantum criticality at high temperature revealed by spin echo. / 自旋回波中的高溫量子臨界現象 / CUHK electronic theses & dissertations collection / Quantum criticality at high temperature revealed by spin echo. / Zi xuan hui bo zhong de gao wen liang zi lin jie xian xiang

January 2013 (has links)
當一個宏觀量子系統的基態因為一個參數的變動產生劇烈的變化時,量子臨界現象會伴隨出現。量子臨界現像是指示新物理產生的重要標誌。在傳統觀測方法裡,量子臨界現像只有在零溫或者低溫下才能被觀測到(這裡低溫是相對於系統中相互作用強度而言的)。我們發現,一個量子探針,如果它的相干時間足夠長,在高溫下依然可以探測到量子臨界現象。特別是,自旋回波可以移除熱漲落效應,從而揭示量子漲落中的臨界現象,而無需把系統冷卻到極低溫度。我們先採用一個嚴格可解模型,即一維橫場伊辛模型演示了在高溫下通過自旋回波揭示量子臨界現象的可能性。臨界行為可以通過嚴格解計算來研究,並可用噪音譜高斯近似法加以理解。通過對噪音譜的分析,我們發現,為觀測到量子臨界現象,傳統方法中所需的溫度(TQc )和探針退相干測量中所需的相干時間( tQc)存在對應關係, 即TQc~ l/tQc 並遠小於系統的相互作用強度。例如,有毫秒或者秒量級相干時間的探針可以用來探測到原本在10 ⁻⁹ K或者1O⁻¹² K溫度下才能看到的量子臨界現象而無需降低系統的溫度。這個發現提供了一種新的研究量子物質的方法。 / 我們還發明了一個用法拉第旋轉回波譜(FRES) 研究透明材料中的自旋噪音的方案,是一種關於測量法拉第旋轉魚漲落的方法。FRES通過抑制熱漲落展現高溫下的量子漲落。它使用的原理和核磁共振中的自旋回波類似。我們用一種稀土化合物LiHoF₄測試了我們的理論。FRES得到的量子漲落在相界上有一個增強的效應。FRES可以被推廣到更複雜的配置,對應核磁共振以及電子自旋共振中的更複雜的動力學去耦操控。以此,我們可以得到更多磁性材料的結構和動力學性質方面的信息。 / Quantum criticality occurs when the ground state of a macroscopic quantum system changes abruptly with tuning a system parameter. It is an important indicator of new quantum matters emerging. In conventional methods, quantum criticality is observable only at zero or low temperature (as compared with the interaction strength in the system). We find that a quantum probe, if its coherence time is long, can detect quantum criticality of a system at high temperature. In particular, the echo control over a spin probe can remove the thermal fluctuation effects and hence reveal the critical quantum fluctuation without requiring low temperature. We first use the exact solution of the one-dimensional transverse-field Ising model to demonstrate the possibility of detecting the quantum criticality at high temperature by spin echo. The critical behaviors have been calculated using the exact solution and understood with the noise spectrum analysis in the Gaussian noise approximation. Using the noise spectrum analysis, we establish the correspondence between the necessary low temperature (TQC) in conventional methods and the necessary long coherence time (tQC) in probe decoherence measurement to observe the quantum criticality, that is, TQC ~ 1/tQC and much less than the interaction strength of the system. For example, probes with quantum coherence time of milliseconds or seconds can be used to study, without cooling the system, quantum criticality that is previously known only observable at extremely low temperatures of nano- or pico-Kelvin. This finding provides a new possibility to study quantum matters. / We also designed a scheme of Faraday rotation echo spectroscopy (FRES) that can be used to study spin noise dynamics in transparent materials by measuring the fluctuation of Faraday rotation angles. The FRES suppresses the static part of the noise and reveal the quantum fluctuations at relatively high temperature, which shares the same idea of the spin echo technique in nuclear magnetic resonance (NMR). We tested our theory on a rare-earth compound LiHoF₄.The quantum fluctuation obtained by FRES gives an enhanced feature at the phase boundary. The FRES can be straightforwardly generalized to more complicated configurations that correspond to more complex dynamical decoupling sequences in NMR and electron spin resonance, which may give us more extensive information on the structural and dynamical properties of magnetic materials. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Chen, Shaowen = 自旋回波中的高溫量子臨界現象 / 陳少文. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 73-80). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese. / Chen, Shaowen = Zi xuan hui bo zhong de gao wen liang zi lin jie xian xiang / Chen Shaowen. / Abstract --- p.1 / 摘要 --- p.3 / Acknowledgment --- p.4 / Chapter 1 --- Introduction --- p.5 / Chapter 1.1 --- Motivation --- p.5 / Chapter 1.2 --- Thesis outline --- p.9 / Chapter 2 --- Central Spin Decoherence Problem --- p.11 / Chapter 2.1 --- Introduction --- p.11 / Chapter 2.2 --- Spin Echo --- p.14 / Chapter 2.3 --- Noise spectrumapproach --- p.14 / Chapter 3 --- Criticality in One-dimensional Transverse Field Ising Model --- p.17 / Chapter 3.1 --- Introduction --- p.17 / Chapter 3.2 --- TheModel and the Exact Solution --- p.19 / Chapter 3.3 --- Results fromexact solution --- p.22 / Chapter 3.4 --- Noise spectrumapproach --- p.23 / Chapter 3.5 --- Time-inverse temperature correspondence --- p.24 / Chapter 3.6 --- Critical exponents --- p.26 / Chapter 3.7 --- More Discussions --- p.30 / Chapter 3.7.1 --- Noise spectra --- p.30 / Chapter 3.7.2 --- Finite probe-bath coupling effect --- p.30 / Chapter 3.7.3 --- Revivals in FID --- p.31 / Chapter 3.8 --- Perspectives for experimental observation --- p.32 / Chapter 3.9 --- Summary --- p.33 / Chapter 4 --- Faraday Roation Echo Spectroscopy --- p.39 / Chapter 4.1 --- Introduction --- p.39 / Chapter 4.2 --- Faraday rotation --- p.41 / Chapter 4.3 --- Faraday rotation echo --- p.44 / Chapter 5 --- Faraday rotation echo of lithium holmium tetrafluoride --- p.47 / Chapter 5.1 --- Introduction --- p.47 / Chapter 5.2 --- Lithium Holmium tetrafluoride: LiHoF₄ --- p.48 / Chapter 5.3 --- Faraday rotation echo spectroscopy --- p.52 / Chapter 5.4 --- Summary --- p.54 / Chapter 6 --- Conclusion and Future work --- p.55 / Chapter Appendix --- p.57 / Chapter A. --- Exact solution of 1D Transverse-field Isingmodel --- p.57 / Chapter B. --- Calculation of the magnetic susceptibility --- p.64 / Chapter C. --- Faraday Rotation --- p.66 / Bibliography --- p.73
107

A Lacanian perspective on selections from into the woods

Howie, Tyler 30 June 2018 (has links)
This thesis examines selections from Stephen Sondheim and James Lapine’s Into the Woods. It begins with an investigation of meaning (both musical and not) and Lacanian psychoanalysis, before moving on to analyses of four songs from the musical: “I Know Things Now”; “Any Moment (Part I)”; “Any Moment (Part II)”; and “Moments in the Woods.” In each of these analyses, this thesis brings musical theater to the interpretive process by continually zooming in; it begins with the drama and moves to the lyrics, providing a clear picture of the narrative to interpret from a Lacanian perspective. It then, as its goal, turns to the music to find this Lacanian narrative reflected in the music. The analysis of “I Know Things Now” explores the concept of the Lacanian symptom, and the effect that a symptom has on the subject. The analysis of the remaining three songs treats them as a group, analyzing a secondary story arch between two characters. The analysis of the trio of songs explores the Lacanian concept of the objet petit a and the associated circuit of desire, and how each of the two characters in the trio interacts with these concepts.
108

The midrange estimator in symmetric distributions

Sundheim, Richard Allen January 2010 (has links)
Digitized by Kansas Correctional Industries
109

Recontextualizing Culture, Power, and Change within MNCs

Belal, Nacera Catherine 12 April 2019 (has links)
<p> The current state of the global economy is in constant transformation. This transformation results in new industries, technologies, and markets. In order to effectively maintain relevance throughout these transformations, organizations must be equipped with the ability to manage change and foster innovation. An organization that is unable to adapt to the rapid changes taking place in this economy will be at greater risk for failure. Context, whether it be cultural, geographic, social or a mix of several overlapping dynamics, is the silent decider of organizational paradigms. The process of transferring organizational assets, such as strategy or culture, from one context to another, is known as recontextualization. This thesis seeks to address the significance of recontextualized organizational assets within a Multinational Corporation (MNC) and the impact on its employees and management structures. The case study will examine how recontextualization shapes a French Headquarter (HQ) - US subsidiary relationship, and more specifically how this contextual dynamic impacts the reception of a HQled change management mission. The conclusion of this thesis will provide perspective for future attempts at collaborative change must integrate greater awareness of recontextualization, particularly during their planned strategic organizational transformation. The supporting research presented throughout this work encompasses interviews with organizational development leaders, cross-cultural management and recontextualization experts, as well as employee testimonials and an autoethnography illustrating the complexities of the HQ-subsidiary relationship.</p><p>
110

Geometric knot theory.

January 2004 (has links)
Hui, Wing San. / Thesis submitted in: November 2003. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 58-60). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.2 --- Outline of Thesis --- p.2 / Chapter 2 --- Basic Knowledge of Knot Theory --- p.3 / Chapter 2.1 --- Preparation --- p.3 / Chapter 2.1.1 --- "Knots, Knot Equivalence and Isotopic Knot" --- p.3 / Chapter 2.1.2 --- Tame and Wild Knots --- p.5 / Chapter 2.2 --- Some Invariants and Quantities about Knot --- p.7 / Chapter 2.2.1 --- Projection of Knot and Crossing Number --- p.7 / Chapter 2.2.2 --- Braids and Braid Index --- p.7 / Chapter 3 --- Minimal Stick Number --- p.11 / Chapter 3.1 --- History and Definition --- p.11 / Chapter 3.2 --- Minimal Stick Number on Some Simple Knots --- p.12 / Chapter 3.3 --- Some Theorems on the Minimal Stick Number --- p.14 / Chapter 4 --- Superbridge Index --- p.22 / Chapter 4.1 --- "Definitions of Bridge Index, Superbridge Index and Total Curvature" --- p.22 / Chapter 4.2 --- Superbridge Index and Braid Index --- p.25 / Chapter 4.3 --- "Relations between Bridge Index, Superbridge Index and Total Curvature" --- p.29 / Chapter 4.4 --- Superbridge Index and Minimal Stick Number --- p.36 / Chapter 5 --- The Geometric Knot Space --- p.37 / Chapter 5.1 --- Definition of the Geometric Knot Space --- p.37 / Chapter 5.2 --- "Geometric Equivalence and Topological Properties of the Geometric Knot Space, Geo(n)" --- p.39 / Chapter 5.3 --- "The Spaces Geo(3), Geo(4) and Geo(5)" --- p.40 / Chapter 5.4 --- Topology of the Space Geo(6) --- p.43 / Chapter 6 --- Concluding Remarks --- p.52 / Chapter 6.1 --- Other Results on the Minimal Stick Number --- p.52 / Chapter 6.2 --- Minimal Stick Number and Superbridge Index of the Torus Knot --- p.54 / Chapter 6.3 --- Explorations of the Geometric Knot Spaces --- p.56 / Bibliography --- p.58

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