Peptide-based hidden Markov model for peptide fingerprint mapping.

Access: Use of this item is restricted to the UNT Community
Peptide mass fingerprinting (PMF) was the first automated method for protein identification in proteomics, and it remains in common usage today because of its simplicity and the low equipment costs for generating fingerprints. However, one of the problems with PMF is its limited specificity and sensitivity in protein identification. Here I present a method that shows potential to significantly enhance the accuracy of peptide mass fingerprinting, using a machine learning approach based on a hidden Markov model (HMM). This method is applied to improve differentiation of real protein matches from those that occur by chance. The system was trained using 300 examples of combined real and false-positive protein identification results, and 10-fold cross-validation applied to assess model discrimination. The model can achieve 93% accuracy in distinguishing correct and real protein identification results versus false-positive matches. The receiver operating characteristic (ROC) curve area for the best model was 0.833.
Date: December 2004
Creator: Yang, Dongmei
System: The UNT Digital Library

Voting Operating System (VOS)

Access: Use of this item is restricted to the UNT Community
The electronic voting machine (EVM) plays a very important role in a country where government officials are elected into office. Throughout the world, a specific operating system that tends to the specific requirement of the EVM does not exist. Existing EVM technology depends upon the various operating systems currently available, thus ignoring the basic needs of the system. There is a compromise over the basic requirements in order to develop the systems on the basis on an already available operating system, thus having a lot of scope for error. It is necessary to know the specific details of the particular device for which the operating system is being developed. In this document, I evaluate existing EVMs and identify flaws and shortcomings. I propose a solution for a new operating system that meets the specific requirements of the EVM, calling it Voting Operating System (VOS, pronounced 'voice'). The identification technique can be simplified by using the fingerprint technology that determines the identity of a person based on two fingerprints. I also discuss the various parts of the operating system that have to be implemented that can tend to all the basic requirements of an EVM, including implementation of the memory manager, …
Date: December 2004
Creator: Venkatadusumelli, Kiran
System: The UNT Digital Library

Brownian Movement and Quantum Computers

Access: Use of this item is restricted to the UNT Community
This problem in lieu of thesis is a discussion of two topics: Brownian movement and quantum computers. Brownian movement is a physical phenomenon in which the particle velocity is constantly undergoing random fluctuations. Chapters 2, 3 and 4, describe Brownian motion from three different perspectives. The next four chapters are devoted to the subject of quantum computers, which are the signal of a new era of technology and science combined together. In the first chapter I present to a reader the two topics of my problem in lieu of thesis. In the second chapter I explain the idea of Brownian motion, its interpretation as a stochastic process and I find its distribution function. The next chapter illustrates the probabilistic picture of Brownian motion, where the statistical averages over trajectories are related to the probability distribution function. Chapter 4 shows how to derive the Langevin equation, introduced in chapter 1, using a Hamiltonian picture of a bath with infinite number of harmonic oscillators. The chapter 5 explains how the idea of quantum computers was developed and how step-by-step all the puzzles for the field of quantum computers were created. The next chapter, chapter 6, discus the basic quantum unit of information …
Date: December 2004
Creator: Habel, Agnieszka
System: The UNT Digital Library

Transplants

Access: Use of this item is restricted to the UNT Community
The body of work originating from this Problem in Lieu of Thesis consists of paintings on canvas that incorporate representations of plant material. The impetus for the paintings was black and white photocopies created from mounds of plant material placed on a copy machine. The resulting copies contained forms that were organic in appearance, but unrecognizable as known objects. Parts of the most interesting and ambiguous copies were used to develop the imagery of the paintings. The new forms served the purpose of creating visual interest from unexpected images. Combined with traditional painting techniques, the selected forms produced paintings of mysterious and playful worlds similar to those parts of the environment not readily accessed, such as galactic space, microscopic organisms, and ocean depths.
Date: December 2004
Creator: Holden, Susan Morrow
System: The UNT Digital Library
Beads on a String: Extended Portraits (open access)

Beads on a String: Extended Portraits

When I was first introduced to photography, I was mainly drawn to landscape imagery. I enjoyed being a solitary spectator. Over time, inclusions of figurative elements became more and more apparent in my work. I purposefully began to incorporate a figure into my landscapes, ascribing to it a certain nostalgia and a sense of isolation I was experiencing on many levels at that time. Before long, I felt disconnected from these images because of their ambiguity and generalization. I found myself craving more content and personal commitment in my photography. At the end 2003, I started experimenting with a 4" x 5" format camera, which forced me, to some extent, to change my way of photographing and seeing. That is how the beginning of this new body of work was born. I was accustomed to shooting with a 35 mm camera, which allowed me to be spontaneous, quick and immediate. I permanently switched to a large format. I could see myself benefiting from this change. I lost some of the spontaneity that a 35 mm format offers but I gained the beauty of working with larger negatives and the endless possibilities of view camera movements. Thanks to this technical transformation, …
Date: December 2004
Creator: Kolčavová, Gabriela
System: The UNT Digital Library