Thesis (M.S.)--School of Mechanical Engineering, Georgia Institute of Technology, 2005. Directed by Yogendra Joshi. / Joshi, Yogendra, Committee Chair ; Ghiaasiaan, Seyed Mostafa, Committee Member ; Jeter, Sheldon, Committee Member. Includes bibliographical references.

Thesis (M. Eng.)--Carleton University, 1991. / Includes bibliographical references. Also available in electronic format on the Internet.

Thesis (M.S.)--University of California, Berkeley, 1962. / "Engineering and Equipment, UC-38" -t.p. "TID-4500 (17th Ed.)" -t.p. Includes bibliographical references (p. 44).

Thesis (M.S.)--Tennessee Technological University, 2009. / Title from title page screen (viewed on July 16, 2010). Bibliography: leaves 135-143.

Thesis (Ph. D.)--University of Texas at Austin, 2005. / Supervisor: Mary F. Wheeler. Vita. Includes bibliographical references.

Thesis (M.S.)--Rochester Institute of Technology, 2005. / Typescript. Includes bibliographical references (leaves 100-104).

Quantum computers offer great potential for significant speedup in executing certain algorithms compared to their classical counterparts. One of the most promising physical systems in which implementing such a device seems viable are trapped atomic ions. All of the fundamental operations needed for quantum information processing have already been experimentally demonstrated in trapped ion systems. Today, the remaining two obstacles are to improve the fidelities of these operations up to the point where quantum error correction techniques can be successfully applied, as well as to scale up the present systems to a higher number of quantum bits (qubits). This thesis addresses both issues. On the one hand, it decribes the experimental implementation of a high-fidelity two-qubit quantum logic gate, which is the most technically demanding fundamental operation to realise in practice. On the other hand, the presented work is carried out in a microfabricated surface ion trap - an architecture that holds the promise of scalability. The gate is applied directly to hyperfine "atomic clock" qubits in ⁴³Ca⁺ ions using the near-field microwave magnetic field gradient produced by an integrated trap electrode. To protect the gate against fluctuating energy shifts of the qubit states, as well as to avoid the need to null the microwave field at the position of the ions, a dynamically decoupled Mølmer-Sørensen scheme is employed. After accounting for state preparation and measurement errors, the achieved gate fidelity is 99.7(1)%. In previous work, the same apparatus has been used to demonstrate coherence times of T^*₂ ≈ 50 s and all single-qubit operations with fidelity > 99.95%. To gain access to the "atomic clock" qubit transition in ⁴³Ca⁺, a static magnetic field of 146G is applied. The resulting energy level Zeeman-structure is spread over many times the linewidth of the atomic transition used for Doppler cooling. This thesis presents a simple and robust method for Doppler cooling and obtaining high fluorescence from this qubit in spite of the complicated level structure. A temperature of 0.3mK, slightly below the Doppler limit, is reached.

Orientador: Eugênio Spanó Rosa / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-16T06:14:18Z (GMT). No. of bitstreams: 1 GomezBueno_LuisGerardo_M.pdf: 4585840 bytes, checksum: b8ed6708894a46ed052d422f40624935 (MD5) Previous issue date: 2010 / Resumo: Medidas experimentais foram realizadas em uma tubulação de 26 mm de diâmetro interno, com inclinação variável de horizontal a vertical, operando com escoamento de água e ar no padrão intermitente ou "slug". Foram utilizados dois sensores de impedância posicionados 77D e 257D a jusante do misturador de água e ar. As faixas de velocidades superficiais de gás e líquido foram 0,1 m/s a 2,1 m/s e 0,3 m/s a 1,2 m/s, respectivamente. Os ângulos de inclinação da tubulação variaram de 15 em 15 graus desde a horizontal até a vertical. Por meio dos sensores de impedância e de pressão foram determinados os parâmetros: a velocidade do nariz da bolha de ar, o comprimento da bolha e do pistão líquido, a freqüência, o fator de intermitência, a taxa de coalescência e a queda de pressão. Uma análise do comportamento destes parâmetros em função das vazões de água e ar assim como dos ângulos de inclinação é realizada / Abstract: This work analyses experimentally the flow properties of a gas-liquid mixture flowing in the slug regime in inclined lines. The experimental data are collected through a pair of impedance probes placed at 77D and 257D downstream of the air-water mixer in a 26mm ID pipe. During the tests air and water superficial velocities spanned, respectively, from 0,1 m/s to 2,1 m/s and from 0,3 m/s to 1,2 m/s. The tests started with the line positioned at the horizontal, 0 degrees and changed, in steps of 15 degrees each, up to the vertical position or 90 degrees. Along each line position the pressure drop, the bubble velocity, the lengths of the liquid slug and of the elongated bubble, the coalescence rate as well as the frequency of the air-water structures were measured. This work analyses the effect of the line inclination on the slug flow properties / Mestrado / Termica e Fluidos / Mestre em Engenharia Mecânica

A two-wheeled, single-axle, differentially driven vehicle possesses many salient advantages when compared to traditional vehicle designs. In particular, high traction factor, zero turn radius, and inherent static and dynamic stability are characteristics of this configuration. Drive torque is provided via a swinging reaction mass hanging below the axle. While mechanically simple, the resulting nonlinear vehicle dynamics can be quite complex. Additional design challenges arise if non-pendulating platforms or hardware mounts are required. Ultimately, this vehicle class has great potential in autonomous robotic applications such as mine clearance, planetary exploration, and autonomous remote inspection. This thesis discusses the kinematic and dynamic analyses of this vehicle class and develops design tools including performance envelopes and control strategies. Further, it confronts the stable platform problem and provides one solution while suggesting alternative design concepts for other applications. / Master of Science

Understanding the signaling mechanisms that determine juvenile-to-mature transition and bud fate is vital for controlling tree reproduction. FD-like proteins also appear to be important for initiating reproductive development. In this study, phylogenetic analysis showed that three FD-like genes (FDL1, FDL2, and FDL3) are present in the poplar genome. FDL1 and FDL2 are products of a recent whole genome duplication event while FDL3 escaped such duplication. Yeast two-hybrid assays demonstrated that FT1 and FT2 proteins interact with FDL3 protein, but not with FDL1 or FDL2 protein. Analysis of the expression levels of FD-like transcripts in Populus deltoides via quantitative real-time PCR showed that FDL3 abundantly expresses in the shoot apex where it probably interacts with FT1 in late winter and early spring. Following the duplication event, FDL1 and FDL2 appear to have diverged in function as they express in a number of tissues in the fall, winter, and spring.