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  • Thesis

  • Authors: Lisi, Samuel Thomas (2006)

  • In this thesis, we consider three applications of pseudoholomorphic curves to problems in Hamiltonian dynamics. In a first part, we prove an existence result for homoclinic orbits on a contact-type, critical energy level of an autonomous Hamiltonian, provided that the level is Hamiltonian displaceable. To do this, we transform the problem into a problem of Lagrangian intersection Floer theory. This involves a construction due to Mohnke [34] and some ideas from Legendrian surgery. In particular, we prove a generalization of Sere's result [36] on the existence of homoclinic orbits for an autonomous Hamiltonian system. In a second part, we develop a theory of pseudoholomorphic curves into a singular contact manifold, which represents the critical level of an autonomous Hamiltonian. We...

  • Thesis

  • Authors: Kurdyumov, Aleksey Valeryevich (2006)

  • For several years in our laboratory we have investigated the formal [3 + 3] cycloaddition. This is a condensation reaction that occurs between an unsaturated aldehyde and a 1,3-diketone or equivalent. The reaction results in a new 2H-pyran or 2H-pyridine fused to the diketone. Chapter I of this thesis concentrates on new developments in the area of oxa-[3 + 3] cycloaddition reaction, in particular, Lewis acid catalyzed version of this reaction. Synthetic scope and limitations of this new methodology are discussed. Chapter II describes synthetic approaches towards naturally occurring chromenes and chromanes. Our total syntheses of such compounds, rhododaurichromanic acid A and B, methyl ester of daurichromenic acid and hongoquercin A, are discussed in detail. Unusual, exo-type poly...

  • Thesis

  • Authors: Lu, Meiling (2006)

  • The metabolism, disposition, and toxicity of arsenic are dramatically different in humans and rats. To better understand the chemical and biochemical basis of these differences and the modes of action of arsenic, here I studied the interaction of arsenic species with hemoglobin (Hb) of both humans and rats. Fast gel filtration chromatography combined with inductively coupled plasma mass spectrometry, nanoelectrospray mass spectrometry, and tandem mass spectrometry methods have been developed to facilitate the study. The three metabolically reactive trivalent arsenic species, inorganic arsenite (iAs"), monomethylarsonous acid (MMA"), and dimethylarsinous acid (DMA"), showed increasing binding affinity with the Hb of rats and humans, with relative binding constants of 1:20:95 for rat...

  • Thesis

  • Authors: Haselton, Curt B. (2006)

  • A primary goal of seismic design requirements of building codes is to protect the life safety of building inhabitants during extreme earthquakes. First and foremost, this requires that the likelihood of structural collapse be at an acceptably low level. However, building codes and standards are empirical in nature, which results in the collapse safety of new buildings not being well understood. In this research, we develop the tools and methods to quantitatively assess the collapse risk of reinforced concrete (RC) special moment frame (SMF) buildings designed by the 2003 International Building Code. While RC SMF buildings are the focus on this study, the methodology and many of the tools can be used to assess any type of structural system. This rigorous analytical collapse assessme...

  • Thesis

  • Authors: Liu, Yi-Wen (2005)

  • "Digital Watermarking" refers to the hiding of binary information in signals such as audio record¬ings, images, or video clips. While the dominating technologies utilize small masked changes in the amplitude to hide information in audio, in an alternate approach, this thesis presents a scheme based on frequency modulation. From an input signal, salient sinusoids are identified in its short-time spectra and parametrized by slowly time-varying frequency envelopes. To bear a watermark, the frequency envelopes are modified by quantization index modulation (QIM), a technique that rounds values to signaling grids. Frequency shifts due to QIM are intended to be not objectionable, if noticeable. To this end, the sensitivity of human ears to pitch changes is carefully considered in the desig...

  • Thesis

  • Authors: Al-Shameri, Faleh Jassem (2006)

  • Recent years have witnessed an explosion in the amount of digitally-stored data, the rate at which data is being generated, and the diversity of disciplines relying on the availability of stored data. Massive datasets are increasingly important in a wide range of applications, including observational sciences, product marketing, and the monitoring and operations of large systems. Massive datasets are collected routinely in a variety of settings in astrophysics, particle physics, genetic sequencing, geographical information systems, weather prediction, medical applications, telecommunications, sensors, government databases, and credit card transactions. Data mining associated with massive datasets presents a major problem to the serious data miner. Datasets on the scale of terabyt...

  • Thesis

  • Authors: Fu, Zhe (2006)

  • The code reuse problem is a common software engineering problem in scientific computing. As a prevailing programming language in many scientific fields, Fortran does not provide support to address this problem. One particular reason is that Fortran lacks the support for generic programming. By applying programgeneration techniques, we developed two approaches to address the code reuse problem. The first approach is to design a program generator for the equation-based specification of subroutines that can be generic in the dimensions of arrays, parameter lists, and called subroutines. We apply that approach to a real-world problem in scientific cpmputing, which requires the generic description of inverse ocean modeling tools. on addition to a compiler that can transform generic speci...

  • Thesis

  • Authors: Dang, Jiangbo (2006)

  • Due to the convergence of industrial demands for business-process and supply-chain management and recent results in multiagent systems, autonomous software services, and the Semantic Web, Web services are becoming the main focus for the next generation of the Internet. They will behave like intelligent agents by composing themselves cooperatively into workflows. A workflow is a set of services that execute by carrying out specified control and data flows. Agents are persistent active entities that can perceive, reason, and act in their environment, and communicate with other agents. Agents can interact autonomously across enterprise boundaries and, when thought of as services, provide a new way to achieve programming-in-the-large. Agents interact with other agents through negotiatio...