The ScholarsArchive@OSU digital repository system captures, stores, indexes, preserves, and distributes digital research material. http://http://ir.library.oregonstate.edu:80/xmlui 2013-05-25T00:05:35Z 2013-05-25T00:05:35Z Ostertag-Hill, Claire http://hdl.handle.net/1957/38726 2013-05-24T23:52:15Z 2013-05-24T00:00:00Z

Investigation of the genetic differences between bovine herpesvirus type 1 variants and vaccine strains Ostertag-Hill, Claire Although an efficacious bovine herpesvirus type-1 (BHV-1) vaccine has been used for many years, BHV-1 vaccine-related abortion and respiratory disease have been occurring in a rising number of herds. To investigate whether isolates from BHV-1 vaccination with adverse effects are identical to the wild type virus or vaccine virus, regions of the thymidine kinase (TK) gene prone to mutation were examined. Two sets of PCR primers were used to investigate two unique polymorphisms of the TK gene in 35 BHV-1 isolates. The DNA polymorphisms in the TK gene were determined by Sanger sequencing of PCR amplicons and the sequence was analyzed with Geneious software. All BHV-1 isolates and vaccine were found to have TK genes that are different from the wild type virus. Over 50% of the sequenced BHV-1 isolate has TK genes that are different from vaccine strains, with 27% having genetic variation in region 1 of TK and 55% in region 2 of TK. This study suggests that BHV-1 isolates have genetic similarity with vaccine virus but have variation within TK genes, which may have resulted from mutations occurred within the vaccinated animals or from infection with a strain similar to the vaccine virus.

2013-05-24T00:00:00Z Talwalkar, Sumit A. http://hdl.handle.net/1957/38725 2013-05-24T22:00:33Z 2013-05-21T00:00:00Z

Modeling and analysis of spur structure of digital-to-time conversion based frequency synthesizers Talwalkar, Sumit A. Frequency synthesizers are critical components of all communication systems. This thesis considers the issue of undesirable frequency spurs of a relatively recent type of frequency synthesis architecture called digital-to-time conversion (DTC). The DTC-based frequency synthesis architecture has important performance benefits over older frequency synthesizers, such as fast frequency switching, large frequency range and fine frequency resolution. A DTC-based frequency synthesizer requires less power than a traditional direct synthesis based synthesizer with comparable frequency range, resolution and switching time. The DTC architecture is also easily scalable to newer low-cost digital complementary metal-oxide-semiconductor (CMOS) integrated circuit (IC) fabrication technologies. However, the DTC architecture suffers from an important undesirable characteristic: sub-harmonic spurious tones, hereafter, referred to as spurs. Spurs have undesirable effects in both the transmitter and the receiver. In a transmitter, spurs create an out-of-band emission of power that may breach the spectral emission mask set by regulatory agencies to enable co-existence of multiple transmitters in a crowded frequency spectrum. In a receiver, an inopportune-located spur in the local oscillator (LO) signal can mix an out-of-band strong interfering signal into the baseband on top of a mixed-down weak desirable signal. Unlike harmonic spurs that are known to be at multiples of the carrier frequency, sub-harmonic spurs are especially problematic as they have been difficult to predict as part of the design process. In fact, the spur patterns for most pairs of closely placed desired output frequencies for a DTC-based frequency synthesizer are seemingly unrelated. While one output frequency setting might have an output spectrum with only a few spurs, many other close-by output frequency settings might have output spectra with many weaker spurs. The primary contribution of this thesis is the development of spur creation models and analysis tools that can predict spur spectrum and spur power levels for a DTC-based frequency synthesizer. This is an important contribution for assuring achievable performance of frequency synthesizer during the design process. The modeling approach has been successful in accounting of more than 99% of spur spectral locations. Predicted power levels for more than 95% are within 10 dB of actual fabricated DTC-based frequency synthesizer ICs. The results developed in this thesis allow for an understanding of the relationship between spur patterns for different selected output frequencies. In the research reported in this thesis, the spur spectrum for a selected output frequency is shown to be due to periodic occurrences of errors in the locations of rising and falling edges of the output signal. Error sequences for different selected output frequencies are shown to be related in a way that can be exploited by application of the axis-scaling property of the Discrete Fourier Transform (DFT). The axis-scaling property of the DFT relates the transforms of two sets of sequences that are predictably permutated versions of each other. Their respective transforms are also (differently) permutated versions of each other. One key insight made in this thesis is the discovery that the time-domain errors for all output frequencies can be classified into a very small number of error sequence classes. All error sequences within a class are shown to be predictable permutations of each other. This insight along with the DFT axis-scaling property permits the respective spur spectra to be classified into error spectra classes. All error spectra within a spur spectra class are predictable permutations of each other. There are two sources of edge errors: quantization error and buffer delay errors. This classification of spur spectra to a few classes is shown to be possible for both sources of errors. In this thesis, the case of quantization-only error is considered first. The analysis is then extended to the case when both sources of error are present. As a result of the modeling and analytical techniques developed for spur spectra classification described in this thesis, design tools have been created to predict the spur spectra of DTC-based synthesizer designs for all possible selected output frequencies. Graduation date: 2013

2013-05-21T00:00:00Z Gokhale, Jayendra http://hdl.handle.net/1957/38724 2013-05-24T21:35:21Z 2013-05-15T00:00:00Z

The behavior of economic agents and market performance Gokhale, Jayendra This dissertation addresses issues concerning the behavior of firms, which has significant effects on performance. In the first study, we empirically investigate the effect of the reduction in number of firms on price competition in the U.S. macro-brewing industry. The number of macro brewing firms decreased from 766 in 1935 to about 20 today. Major national brewers such as Anheuser Busch, Miller and Coors have continually gained market share. In spite of the reduction in number of competitors, market power remains low. There is evidence in the literature that changes in marketing and production technology have favored large brewers. However, an intense war of attrition has historically kept prices low. As this war wound down in the late 1980s, the number of firms diminished unabated. Many theoretical models of oligopoly behavior suggest that a decrease in number of firms reduces competition and increases price. We use two different techniques and find that price competition remains high even though the number of rivals has fallen. In the second study, we estimate the life cycle of movies in theaters. In this market there is no price competition. The primary form of competition is through product differentiation in the form of product quality, advertising and genre. We find evidence that the longer the duration of movies in theaters, the greater is the probability of death. Secondly, we also observe that a movie with either higher advertising expenditures or better product quality has a better probability of survival. Thirdly, we find that a movie which faces stiffer competition from substitutes is more likely to have a greater decay of sales. In the third study, we investigate the effect of product recalls due to an unintended acceleration problem on the market value of Toyota. We investigate four cases related to unintended acceleration problems. We find evidence of a significant negative effect on the market value of Toyota in the major recall in January 2010. Following this recall, there were Congressional hearings and testimony of the CEO of Toyota. Congress requested the National Highway Traffic Safety Administration (NHTSA) to investigate whether or not the fix recommended by Toyota was sufficient to solve the problem. When the NHTSA study concluded that Toyota had correctly solved the problem, the market value of Toyota substantially increased. Graduation date: 2013

2013-05-15T00:00:00Z Avery, Bonnie E. http://hdl.handle.net/1957/38723 2013-05-24T06:13:12Z 2004-01-01T00:00:00Z

Forestry Avery, Bonnie E. A broad definition of forestry would be "the study of trees, forests, and their use by people." Modern "science-based forestry" is thought to have begun in the nineteenth century when Europeans looked to specialists to address questions of wood supply and extraction both in their forests at home and in their colonies. The threat of forest loss and wood scarcity resulted in concern for increased forest growth and management techniques for improved yield. By 1891 the United States had established publicly owned forest reserves. In 1900 the Society of American Foresters was established, as was the first School of Forestry in North American at Yale University. The U.S. Forest Service was formed three years later, and this combination of professional, scholarly, and governmental resources constitute the core of U.S. forestry research today. Since the mid-1940s the scope of forestry has grown in response to economics, demography, politics, and social change as well as developments in related fields of study. While at one time German was the primary language of forestry, since World War II most research is reported in English. Knowledge of inter-national research and practices has grown in importance since the 1980s. In addressing global forest concerns, international and local researchers have begun to "discover" reservoirs of indigenous knowledge concerning forests and their use. Modern forestry education has a tradition of integrating concepts from a variety of disciplines and creating new specialties. These include forest genet-ics, forest ecology, forest recreation, forest economics, forest engineering, urban forestry, plantation forestry, forest pathology, and wood science. The questions addressed by forestry are often interdisciplinary or require a deep understanding of a complementary discipline. As a result, a forest science collection will not be useful in isolation from access to sound collections in the natural, environ-mental, and agricultural sciences. Likewise, a wood science or forest engineer-ing collection will rely on user access to collections in the physical sciences and civil, mechanical, and chemical engineering. Finally, to address the interaction of humans and "forest resources," whether looking at income generation, recreational use, traditional knowledge and practices, or conservation strategies, a forestry researcher will need access to collections in the social sciences. Given these assumptions about access to other collections, we can define a distinct serial literature for forestry. It is defined by the history of forestry and as a result is composed largely of government document series, international, and nongovernmental organization reports as well as trade, scholarly professional, and, more recently, scholarly commercial journals. The selected list of periodicals included here does not include government publications, although these are an important source of technical as well as scientific information. Governmental agencies such as the regional research and experiment stations of the U.S. Forest Service are vital sources of information on all aspects of forestry. Series titles such as the regional General Technical Reports are numerous. They are now published electronically in full-text and are available from the Forest Service web site. Canadian libraries will benefit from their easy access to this literature and that of the National Research Council of Canada's many serial publications. Although they are important sources of information, statistical series and serials available from nongovernmental, nonprofit international organizations and research institutions have not been included in this listing. Several statistical series and The State of the World's Forests are available as searchable datasets and in full-text online from the Food and Agriculture Organization (FAO) Forestry Sector web site. There are numerous serial publications now available via the Internet from other nongovernmental, nonprofit agencies. These are particularly important for coverage of "international forestry." The FAO Forestry Sector web site will help identify and serve as a portal to many of these resources as will the "AgNIC Forestry" web site. The selection of scholarly, academic, and trade journals is primarily representative and by no means exhaustive. Added to the list of forestry titles with this edition are Agroforestry Systems and International Review of Forestry as representative titles for "international forestry," as well as Forest Policy and Economics and the JAWA Journal. Deleted from the list is Forestry Source because the nonmember highlights are now available from the Society of American Foresters web site. In reviewing the periodicals from the 11th edition and considering new titles, I looked for titles widely held by other libraries. In 2001, faculty members in the College of Forestry at Oregon State University were asked to list their most used or "top ten" journals. This listing provided me with evidence of the multidisciplinary underpinnings of forestry and new titles for consideration. In assessing scholarly titles, I looked for titles with high impact factors or a high journal citation half-life using the Journal Citation Reports from the Institute for Scientific Information. When deciding between comparable titles I took into consideration the journal subscription price, and gave preference to professional society publications over journals from commercial publishers. In the earlier editions of this section, Carol C. Green of the University of Washington has recommended using Literature of Forestry and Agroforestry, published by Cornell University Press in 1996.1 would like to acknowledge that I too have made use of this bibliography and reiterate its importance to anyone managing a forestry collection. In addition to giving a useful history of forestry, it identifies both monographs and serials that have provided the foundation for "science-based forestry." Posted by permission of Cambridge Scientific Abstracts (CSA). (c) CSA 2004. All rights reserved.

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