Ninety-five oriented samples were obtained from nine Recent Cascade lava flows in Oregon. Directions and intensities of remanent magnetization were measured on a spinner magnetometer which measures directions of magnetization to within 1.2° s.d. Angle measurements were plotted graphically using an equal area projection. Mean directions and statistics were calculated by digital computer. Samples were demagnetized in alternating magnetic fields while being rotated in a two axis tumbling device. All flow means, except one, calculated from the original magnetization vectors are distinct from the present geomagnetic field direction. A correspondence is found between scatter observed in a flow and the type of outcrop sampled (whether natural or man-made). This is believed to be a consequence of excessive blockiness and aa characteristics of the lavas. Results of demagnetization tests indicate low secondary magnetizations. Stability is indicated by lack of anisotropy, lack of isothermal and chemical remanent magnetizations, low viscous magnetization, and divergence of flow means from the present field direction. Flow mean directions for five dated flows are used to trace the secular variation of the paleomagnetic field back to 3000 B.P. This secular variation curve agrees with data taken in southwestern United States for the same period of time. It has generally been found that Recent mean pole positions are coincident with the geographical pole within the limits of error of the data. This study yielded a mean direction distinct from an axial dipole direction. However, the age span is limited as eight of the nine flows have ages between 300 and 3850 years. / Graduation date: 1968

This thesis presents an efficient computational voxelization approach that utilizes the graphics pipeline. Our approach is hybrid in that it performs a precise gap-free computational voxelization, employs fixed-function components of the GPU, and utilizes the stages of the graphics pipeline to improve parallelism. This approach makes use of the latest features of OpenGL and fully supports both conservative and thin voxelization. In contrast to other computational voxelization approaches, this approach is implemented entirely in OpenGL, and achieves both triangle and fragment parallelism through its use of both the geometry and fragment shaders. A novel approach utilizing the graphics pipeline to complement geometric triangle intersection computations is presented. By exploiting features of the existing graphics pipeline we are able to rapidly compute accurate scene voxelization in a manner that integrates well with existing OpenGL applications, is robust across many different models, and eschews the need for complex work/load-balancing schemes. / Graduation date: 2013

Thesis (M.S.)--University of Florida, 2001. / Title from first page of PDF file. Document formatted into pages; contains vii, 45 p.; also contains graphics. Vita. Includes bibliographical references (p. 43-44).

Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

In this study, we consider a relay network, with two transceivers and r relay nodes. We assume that each of relays and the two transceivers have a single antenna. For establishing the connection between these two transceivers, we propose a two-way relaying scheme which takes three phases (time slots) to accomplish the exchange of two information symbols between the two transceivers. In the first and second phases, the transceivers, transmit their signals, toward the relays, one after other. The signals that are received by relays are noisy versions of the original signals. Each relay, multiplies its received signal by a complex beamforming coefficient to adjust the phase and amplitude of the signal. Then in the third phase, each relay transmits the summation of so-obtained signals to both transceivers. Our goal is to find the optimal values of transceivers’ transmit powers and the optimal values of the beamforming coefficients by minimizing the total transmit power subject to quality of service constraints. In our approach, we minimize the total transmit power under two constraints. These two constraints are used to guarantee that the transceivers’ receive Signal-to-Noise Ratios (SNRs) are above given thresholds. To solve the underlying optimization problem, we develop two techniques. The first technique is a combination of a two-dimensional search and Second-Order Convex Cone Programming (SOCP). More specifically, the set of feasible values of transceivers’ transmit powers is quantized into a sufficient fine grid. Then, at each vertice of this grid, an SOCP problem is solved to obtain the beamforming coefficients such that for the given pair of transceivers’ transmit powers, the total transmit power is minimized. The pair of the transceivers’ transmit powers, which result in the smallest possible value of the total transmit power, leads us to the solution of the problem. This approach requires a two-dimensional search and solving an SOCP problem at each point of the corresponding two-dimensional grid. Thus, it can be prohibitively expensive in terms of computational complexity. As a second method, we resort to a gradient based steepest descent technique. Our simulation results show that this second technique performs very close to the optimal two-dimensional search based algorithm. Finally we compare our technique with multi-relay distributed beamforming schemes, previously developed in literature and show that our three-phase two-way relaying scheme requires less total power as compared to the two-phase two-way relaying method. On the other hand, the two-phase two-way relaying achieves higher data rates when compared with three-phase two-way relaying for the same total transmit power. Also, we observe that the three-phase scheme has more degrees of freedom while multi-relay distributed beamforming schemes, previously developed in literature appears to be more bandwidth efficient. / UOIT

In recent years, marine natural products in drug development increasingly wide range of applications. Both Taiwan's geographical location and climate are creating a rich marine biodiversity. Hence there is needed to construct a marine natural product database which with Taiwan features. The goal of this study is to establish a Taiwan's marine natural product database, with preliminary collected Formosan soft coral diterpenoids natural products from Taiwan for drug development features. The database included normal physical and chemical properties of compounds and biological activity assay from literature. Key project for the database is to construct three-dimensional structure information for marine natural products. In this study, it was to build and to check the correct three-dimensional structure by use of computer simulation study comparing with nuclear magnetic resonance (NMR) spectroscopy information from literature. The identification of the folding errors in three-dimensional structure of various compound skeleton types by computer was also discussed. And there was also discussed the relationship between potential energy and three-dimensional structure of compounds by compare with computer simulated structure and NMR structure.

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The purpose of this thesis is to develop a high power, compact all solid-state blue laser, which is applicable in micro machining, LIDA, underwater ranging, biochemical techniques and so forth. The passive Q-switching technique, which is known to be a low-cost and simple method to raise the laser peak power was employed in this thesis. In the mean time, the intracavity-doubling technique was integrated to achieve the non-linear frequency conversion for generating blue laser at low cost. Based on our research finding, the reabsorption loss due to thermal effect and a paucity of suppression at wavelength of 1064 nm on laser mirrors could cause the four-level oscillation at 1064 nm instead of three-level oscillation at 914nm. Improvement in heat dissipating system, and suppression at wavelength of 1064 nm on mirror coating has led to a success in developing a quasi-three-level blue laser with peak power of 114W at wavelength 473 nm. A modified rate equation model of the quasi-three level passively Q-switched blue lasers was developed as well, in which the influence of the re-absorption loss in the gain medium and its intracavity frequency doubling were both considered. The influence of reabsorption loss upon the laser power deduction was studied by numerical simulation in order to optimize the laser performance.

The asymptotic behavior of the wave functions of three charged particles has been investigated. There are two different types of three-body scattering wave functions. The first type of scattering wave function evolves from the incident three-body wave of three charged particles in the continuum. The second type of scattering wave function evolves from the initial two-body incident wave. In this work the asymptotic three-body incident wave has been derived in the asymptotic regions where two particles are close to each other and far away from the third particle. This wave function satisfies the Schrodinger equation up to terms O(1/3pa), where pa is the distance between the center of mass of two particles and the third particle. The derived asymptotic three-body incident wave transforms smoothly into Redmond’s asymptotic incident wave in the asymptotic region where all three particles are well separated. For the scattering wave function of the second type the asymptotic threebody scattered wave has been derived in all the asymptotic regions. In the asymptotic region where all three particles well separated, the derived asymptotic scattered wave coincides with the Peterkop asymptotic wave. In the asymptotic regions where two particles are close to each other and far away from the third one, this is a new expression which is free of the logarithmically diverging phase factors that appeared in the Peterkop approach. The derived asymptotic scattered wave resolves a long-standing phase-amplitude ambiguity. Based on these results the expressions for the exact prior and post breakup amplitudes have been obtained. The post breakup amplitude for charged particles has not been known and has been derived for the first time directly from the prior form. It turns out that the post form of the breakup amplitude is given by a surface integral in the six dimensional hyperspace, rather than a volume integral, with the transition operator expressed in terms of the interaction potentials. We also show how to derive a generalized distorted-wave-Born approximation amplitude (DWBA) from the exact prior form of the breakup amplitude. It is impossible to derive the DWBA amplitude from the post form. The three-body Coulomb incident wave is used to calculate the reaction rates of 7Be(ep, e)8B and 7Be(pp, p)8B nonradiative triple collisions in stellar environments.