We consider the computational complexity of evaluating the Tutte polynomial of three particular classes of greedoid, namely rooted graphs, rooted digraphs and binary greedoids. Furthermore we construct polynomial-time algorithms to evaluate the Tutte polynomial of these classes of greedoid when they're of bounded tree-width. We also construct a Möbius function formulation for the characteristic polynomial of a rooted graph and determine the computational complexity of computing the coefficients of the Tutte polynomial of a rooted graph.

A kinetic study of the reactions of Group VI-B hexacarbonyls with primary amine and halide ligands was undertaken in order to determine the possible mechanisms of these reactions. As well as the expected dissociative pathway, the reactions with the primary amines were seen to proceed by a concurrent pathway which was dependent upon the ligand concentration. Since nitrogen donor ligands are expected to be poor donor ligands, the mechanism proposed was a "dissociative interchange" mechanism which should not be too dependent upon the nucleophilicity of the ligand. Comparison of the rate constants for the amines studied as well as those of the previously investigated Lewis base ligands indicated all such reactions may proceed through the same mechanism. The similarity in rate constants for the ligand-independent and ligand-dependent pathways supports this mechanism. The rate of formation of the final product was seen to be dependent upon the square of the mercuric halide concentration. Therefore, the conversion of Fe(CO)4(HgX)2 to the final product was proposed to proceed by the successive abstraction by each HgX group of two molecules of mercuric halide. These oxidative elimination reactions are related to a chemical model for the intermediate step in the reduction of dinitrogen to ammonia and their similarities and differences are discussed.

Atualmente, a adição de uma nova função implementada em hardware em um processador não deve impor nenhuma mudança no conjunto de instruções (ISA – Instruction Set Architecture) suportado para atingir melhorias em seu desempenho. O objetivo é manter a compatibilidade retroativa e futura de programas já compilados. Todavia, este fato se torna, muitas vezes, um fator impeditivo para o aprimoramento ou desenvolvimento de uma nova arquitetura. Desta maneira, a utilização de mecanismos de Tradução Binária abre novas oportunidades aos projetistas, já que estes mecanismos permitem a execução de programas já compilados em arquiteturas que suportam conjuntos de instruções diferentes do previsto inicialmente. Assim, para eliminar o custo adicional apresentado por estes sistemas de tradução, será proposto um novo mecanismo de tradução binária dinâmico de dois níveis. Enquanto o primeiro nível é responsável pela tradução de facto das instruções do conjunto nativo para instruções de uma linguagem de máquina intermediária, o segundo nível otimiza estas instruções já traduzidas para serem executadas na arquitetura alvo. O sistema é totalmente flexível, pois pode suportar a tradução de conjuntos de instruções completamente diferentes; assim como a utilização de arquiteturas de hardware com as mais diversas características. Este trabalho apresenta o primeiro esforço nesta direção: um estudo de caso onde ocorre a tradução de código x86 para MIPS (linguagem intermediária), que será otimizado para ser executado em uma arquitetura que realiza reconfiguração dinâmica. Resta demonstrado que é possível manter a compatibilidade binária, com melhoria no desempenho em torno de 45% em média e consumo de energia semelhante ao da execução nativa. / In these days, every new added hardware feature must not change the underlying instruction set architecture (ISA), in order to avoid adaptation or recompilation of existing code. Therefore, Binary Translation (BT) opens new possibilities for designers, previously tied to a specific ISA and all its legacy hardware issues, since it allows the execution of already compiled applications on different architectures. To overcome the BT inherent performance penalty, we propose a new mechanism based on a dynamic two-level binary translation system. While the first level is responsible for the BT de facto to an intermediate machine language, the second level optimizes the already translated instructions to be executed on the target architecture. The system is totally flexible, supporting the porting of radically different ISAs and the employment of different target architectures. This work presents the first effort towards this direction: it translates code implemented in the x86 ISA to MIPS assembly (the intermediate language), which will be optimized by the target architecture: a dynamically reconfigurable architecture. In this work is showed that is possible to maintain binary compatibility with performance improvements on average 45% and similar energy consumption when compared to native execution.

In this study I analyzed the pattern of settlement for known Medio period (A.D. 1200–1450) sites in the Casas Grandes region of Chihuahua, Mexico. Locational data acquired from survey projects in the Casas Grandes region were evaluated within a Geographic Information Systems (GIS) framework to reveal patterns in settlement and site distribution. Environmental and cultural variables, including aspect, cost distance to nearest ballcourt, ecoregion, elevation, local relief, cost distance to nearest oven, cost distance to Paquimé, slope, soil, terrain texture, topographic position index, cost distance to nearest trincheras, vegetation, vegetation variety to 100 meters, vegetation variety to 500 meters, cost distance to nearest intermittent lake, cost distance to nearest intermittent stream, cost distance to nearest perennial lake, and cost distance to nearest perennial stream were calculated for each site in this region. It was expected that the relationships of correspondence between known sites and these variables would provide a quantitative framework that could be used to model the locational probability of unknown sites in the region. Through the use of GIS and statistical analyses, the results of this study were used to produce an archaeological site sensitivity map for this region of northern Mexico.

We investigate the existence of a symmetric singular periodic brake orbit in the equal mass, fully symmetric planar four body problem. Using regularized coordinates, we remove the singularity of binary collision for each symmetric pair. We use topological and symmetry tools in our investigation.

The majority of current multi-label classification research focuses on learning dependency structures among output labels. This paper provides a novel theoretical view on the purported assumption that effective multi-label classification models must exploit output dependencies. We submit that the flurry of recent dependency-exploiting, multi-label algorithms may stem from the deficiencies in existing datasets, rather than an inherent need to better model dependencies. We introduce a novel categorization of multi-label metrics, namely, evenly and unevenly weighted label metrics. We explore specific features that predispose datasets to improved classification by methods that model label dependence. Additionally, we provide an empirical analysis of 15 benchmark datasets, 1 real-life dataset, and a variety of synthetic datasets. We assert that binary relevance (BR) yields similar, if not better, results than dependency-exploiting models for metrics with evenly weighted label contributions. We qualify this claim with discussions on specific characteristics of datasets and models that render negligible the differences between BR and dependency-learning models.

In this dissertation, I present two studies in the field of gravitational wave astrophysics applied to compact binary systems. In the first project, I investigate simulated encounters between a binary system comprised of two stellar mass black holes with a galactic supermassive black hole. It is found that binaries disrupted by the supermassive black hole form extreme mass ratio inspirals (EMRIs), which would begin with very high eccentricity, e ≈ 1 − O(10−2), but circularize dramatically by the emission of gravitational wave radiation. At the time when the stable orbit turns over to a plunge orbit, the EMRIs still have some small residual eccentricity, e ≈ 0.05 on average, which is slightly larger than previous estimates. The surviving binaries are classified based on their final relation with the supermassive black hole. When inspecting the merger lifetime of the surviving binaries, a mean new merger lifetime of ˜ T = 0.8T0 is found. Factoring in this new lifetime with other relevant data, I calculate the merger rate of these systems in the range of the advanced Laser Interferometer Gravitational Wave Observatory to be about 0.25 yr−1, which represents a small percentage of the current predicted CBC rates. In the second project I propose and explore a new method of estimating the radius of the accretion disc in cataclysmic variable binary systems though the use of coupled electromagnetic and gravitational wave observations. By identifying the angle of the hot spot formed by the impact of the accretion stream with the disc, φHS, the radius of the disc can be recovered. I test the proposed method against fully simulated lightcurve output, as well as the true observed AM CVn lightcurve. In both cases, I find our method capable of estimating the disc radius to high precision. I calculate a disc radius of ˆRD/a ≈ 0.476°”0.025 for the fully simulated data and ˆRD/a ≈ 0.481 °” 0.05 for the true lightcurve data. These estimates agree with the accepted value of RD = 0.478a within the uncertainties, and differ from the accepted value by 0.4% and 0.6%, respectively. Because this method does not rely on eclipses, it will be applicable to a much broader population of binaries.

The increasing presence of Chinese international graduate students in American higher education has mandated a closer examination of their multifaceted lives against stereotypes that hinder their efforts to find, transform, or assert their identities in the dominant discourses of American academia and culture. Cross cultural studies of Chinese international students tend to reinforce stereotypes of their writer identities, learner identities, and teacher identities. Examining these various identities discloses dichotomies that read Chinese students’ traits and behaviors as handicaps and thus characterize them as “abnormal” in relation to the “normal” traits and behaviors of Chinese students’ Western counterparts. Whereas Western student writers are described as direct and logical, Chinese student writers are characterized as indirect and illogical. In comparison to the assertive and critical way of thinking that is regarded as the norm among American students, Chinese students are seen as submissive “rote learners.” Conversely, the liberatory, student-centered approach to teaching that is promoted in the American educational system is thought to be antithetical to what is considered to be an authoritarian, teacher-centered approach of Chinese education. Underlying these binaries is an unchallenged gender binary. Deeply entrenched Western notions about masculinity and femininity ultimately lead to a feminization of Chinese identities. Despite the constant critique from various disciplines, dichotomous views of gender persist and consequently lead to misconceptions about Chinese subjectivity in U.S. This project argues that these misconceptions have produced consistently devastating effects on Chinese students and further demobilize them from acculturating themselves into the dominant discourse in the United States. To deconstruct these socially, culturally, and ideologically constructed binaries, this work uses scholarship on subjectivity and identity by Michel Foucault and Homi Bhabha to examine critically how identity is formed and transformed; it also draws heavily on scholarship in rhetoric and composition and in feminist studies to delineate how Chinese students’ various identities are formed and transformed. The goal of this work is to advance a complementary thinking to advocate new conceptions about Chinese students’ various identities and ultimately to allow Chinese students to assume more active agency in their identity transformation process in the U.S.

Historically, in academic literature—sociological and otherwise—surrounding the daily lives of LGBT+ people, people who reject binary gender are very marginally represented. In this study, I specifically seek to understand the way my participants articulate their sense of their gender identities through the stories they tell of their experiences. This study attempts to answer the following questions: What are the stories of gender identity construction for people who reject binary gender? How do they understand the ways they are held accountable to binary gender in the day-to-day? How do they perceive and make meaning of gender in their lives? Through ten in-depth interviews with participants accessed through online groups and snowball sampling, this project reinforces gender surveillance and accountability theories such as West and Zimmerman's. Although participants largely identified the root of their feelings about gender as within their selves, the stories they told about their experiences of gender revealed that interactions with others were important and thus have a large effect on their lives. This indicates that these interactions with others where participants are held accountable to binary gender do have an impact on the ways they construct their gender and selves but because this has been such a consistent part of their lives, participants perceive this as innate to their selves and private feelings.

Orchid growing is a hobby that includes not only acquiring and caring for orchids, but also learning about the diverse care requirements of various orchids, attending meetings of orchid groups, having one’s orchids evaluated by American Orchid Society judges or being a judge, or even creating hybrids. In this way, orchid hobbyists compose a distinctive subculture (Hansen 2000). Yet the activity of orchid growing also forms a nexus between the non-human and the human, two categories that are often constructed as an opposing binary. This thesis focuses on how orchid growing represents both the embedded, institutionalized characteristic of the binary between the non-human and the human and how this binary is actively deconstructed; that is, orchid growers often reinforce this binary through positioning their orchids as a part of “nature” and also blur it by participating in the activity of orchid growing. Through observations of monthly meetings of two local orchid groups and affiliated events and walking tours of individual participants’ orchid growing spaces and semi-structured interviews with them, I show how orchid growing represents such a “hybrid” form of nature (Whatmore 2002). Specifically, the ways in which orchid growers appreciate the novelty of their orchids, care for them, and establish authenticity in orchid growing demonstrates the nuanced ways orchid growing forms a relationship with “nature.”