Digital Commons Network^™

A Sensory-Based Adaptive Walking Control Algorithm For Variable Speed Biped Robot Gaits, Andrew L. Kun

Doctoral Dissertations

A balance scheme for handling variable speed gaits was implemented on an experimental biped. The control scheme used pre-planned but adaptive motion sequences in combination with closed loop reactive control. CMAC neural networks were responsible for the adaptive control of side-to-side and front-to-back balance. The biped performance improved with neural network training. The biped was able to walk with variable speed gaits, and to change gait speeds on the fly. The slower gait speeds required statically balanced walking, while the faster speeds required dynamically balanced walking. It was not necessary to distinguish between the two balance modes within the controller. …

The Effects Of Age And Expertise On Discourse Processing, Lisa Marie Soederberg

Doctoral Dissertations

The paradoxical nature of adult development is that it is marked by a decline in processing capacity but an increase in knowledge. A specialized formulation of increased knowledge that can occur throughout the lifespan is expertise. Because discourse processing is both a method of acquiring domain expertise and is facilitated by domain expertise, the nature of this interrelationship is central to successful aging. However, the processes through which expertise facilitates discourse processing are virtually unexplored within the cognitive aging literature. Four experiments investigating this issue are presented. The first experiment investigated age differences in on-line reading strategies of readers with …

Construction Of An X-Band Electron Nuclear Double Resonance Spectrometer And Partial Characterization Of An Iron Nitrosyl Complex Of Transferrin, Pamela Marie Proulx-Curry

Doctoral Dissertations

An X-band Electron Nuclear Double Resonance (ENDOR) spectrometer was constructed, tested at both room and liquid helium temperatures, and characterized at liquid helium temperature using a vanadyl-imidazole standard.

An iron nitrosyl complex of transferrin was studied. Three methods of generating nitric oxide gas were tested and resulted in no differences in product formation. The g-factors for the rhombic complex--prepared with and without carbonate addition to the buffer--were determined. For the complex prepared with carbonate g$\sb{\rm x}$ = 2.052, g$\sb{\rm y}$ = 2.028, and g$\sb{\rm z}$ = 2.013. For the complex prepared without addition of carbonate g$\sb{\rm x}$ = 2.051, g$\sb{\rm …

A Metric-Based Scientific Data Model For Knowledge Discovery, David T. Kao

Doctoral Dissertations

Scientific data, which include multimedia (e.g., images, audio, and video) and non-standard data (e.g., finger prints and DNA sequences), is characterized by rich and complex inter-instance relationships in addition to the inter-entity relationships found in traditional data. Conventional data models are insufficient for modeling such inter-instance relationships. This thesis proposes a metric-based scientific data model from the notions of data-as-functions and pseudo-quasimetrics, which are used to model inter-entity and inter-instance relationships respectively. Compared to other scientific data models, the metric-based conceptual model can be applied to many data sets where geometric views might not otherwise be available.

A detailed approach …

Modeling Of The Electromagnetic Radiation From Shielded Enclosures With Apertures And Attached Wires In A Real-World Environment, Bruce Roy Archambeault

Doctoral Dissertations

A hybrid modeling technique using the Finite-Difference Time-Domain (FDTD) approach in conjunction with the Method of Moments (MoM) approach was developed to allow simulation of electromagnetic interference (EMI) emissions through apertures due to sources within a shielded enclosure. These apertures can include air ventilation openings, option card slots, mating cover seams, or any other opening in the metal shielded enclosure. Modeled emission results can now be directly compared to U.S. and other countries' regulations to allow engineers to predict compliance before hardware prototypes are built. The effects of the test environment, including ground plane and specified measurement distance, as well …

Contributions To The Theory Of Neighborhoods And Its Applications, Michael Joseph Cullinane

Doctoral Dissertations

Neighborhoods have played a fundamental role in general topology since the birth of the field. This work outlines the historial evolution of the notion of neighborhood and employs neighborhood assignments, weak neighborhood assignments, and a naturally induced notion of duality in a study of non-Hausdorff topological spaces. Neighborhood characterizations of various classes of spaces, among them the developable and the pseudometrizable spaces, are obtained. A generalization of topological spaces based upon a primitive notion of neighborhood is explored and examples are supplied to motivate the investigation.

An Experimental Investigation Of The Effects Of Elastic Modulus And Yield Strength On Fracture Surface Interference In Shear Loaded Cracks, Ronald U. Goulet

Doctoral Dissertations

An experimental process was developed to study the effects of material properties on fracture surface interference in Mode II loaded cracks in 7075 aluminum. 4340 and 8642 steels. Factors studied included elastic modulus, yield strength, mode mixity and fracture surface geometry. An asymmetric four point bend specimen and fixture was developed to apply pure Mode II and mixed Mode I and II loads to edge cracks. Three dimensional displacement fields were measured as a function of applied load using an electro-optical holographic interferometric facility. Stress intensity factors were obtained by fitting observed 2-D field displacements to basis functions derived from …

Talk Before Writing: Oral Rehearsal As A Pre-Writing Strategy For High School Students With Difficulties In Retrieval, Valerie Sebern Aubry

Doctoral Dissertations

This study investigated the effects of oral rehearsal used as a pre-writing strategy by twenty-eight high school students (21 males, 7 females) with difficulties in retrieval. Study participants read texts, wrote summary-response essays, and revised their compositions in two conditions: with rehearsal and without rehearsal. A repeated measures (2 x 2) x (2) design with Passage and Order of Treatment as the between-subject variables, and Condition as the within-subject variable was used to assess differences in compositions.

Eight quantitative measures, with four considered primary, were used to evaluate differences in the quantity, complexity, content, and quality of compositions. Positive changes …

The Role Of Perceived Social Norms On Attitudes And Behavior: An Examination Of The False Consensus Effect, Kathleen Patricia Bauman

Doctoral Dissertations

This paper examined the role of perceived social norms in relation to people's attitudes and behavioral intentions, specifically in regards to the false consensus effect (FCE). People are prone to numerous biases in judgments about peers' beliefs, including overestimating support for their own position (i.e., false consensus). These misperceptions can then shape people's beliefs and guide their behavior. This series of studies assessed the influence of this type of misperception on attitudes and behavioral intentions regarding controversial social issues. Study 1 demonstrated that people displayed false consensus for current social issues. Alterations in wording and order of presentation did not …

Judging Contingencies Accurately: The Effects Of Feedback, Practice, And Self-Efficacy, Steven C. Clark

Doctoral Dissertations

Some psychologists have claimed that people are not good at judging covariation (e.g., Smedslund, 1963; Jenkins & Ward, 1965). This claim, however, has been based on the results of experiments that may not have been optimal for promoting judgmental accuracy (Allan & Jenkins, 1980). Other psychologists have claimed that people are relatively good judges of covariation (e.g., Wasserman, Chatlosh, & Neunaber, 1983; Wasserman & Shaklee, 1984). Common to most of this research is an experimental paradigm in which participants do not ever receive feedback concerning the accuracy of their judgments.

The two experiments in this dissertation were designed to promote …

Student Achievement, Parental Effort And Schooling, Andrew James Houtenville

Doctoral Dissertations

When evaluating public education programs that are aimed at improving student achievement, it is often assumed that a child's family background is an exogenous factor, albeit an important factor. However, parental decisions may be influenced by such programs. It is the assertion of Becker and Tomes (1976) that distortions in parental behavior (time allocation) may be one of the reasons that compensatory education fails to improve student achievement. In short, parents reduce their own effort when school services (schooling) is increased. However, theoretically parental responses are ambiguous; parental effort can increase or decrease in response to increased schooling. This dissertation …

The Effects Of Actual And Perceived Parental Characteristics On Partner Selection And Perception, Glenn Gehar

Doctoral Dissertations

The present studies were designed to examine the template matching hypothesis, a prediction based on Freud's (1927) psychoanalytic theory which proposes that people choose romantic partners who are similar to their opposite-sex parents. While some research has demonstrated that such a phenomenon does exist for physical characteristics (e.g., Jedlicka, 1984), research on this phenomenon in regards to personality dimensions has been relatively inconclusive. The primary objectives of the present studies were to determine (a) the extent to which people choose partners with personalities similar to their opposite-sex parents, (b) the extent to which people perceive that their romantic partners have …

Predation By Nucella Lapillus (Linnaeus, 1758) On Littorina Obtusata (Linnaeus, 1758) And Mytilus Edulis (Linnaeus, 1758), Helena Matthews Cascon

Doctoral Dissertations

Prey preference and recognition by individuals of Nucella lapillus from 13 different populations from New England were studied, to determine if individuals of this species kept on a single prey diet develops a preference for this prey, and if prey availability affects prey recognition in this predator. Individuals from all 13 populations showed a preference for Mytilus edulis over Littorina obtusata in laboratory experiments, including those from a population that prey only on L. obtusata in the field. Individuals from another population were not able to recognize L. obtusata as a prey. N. lapillus kept in a diet of M. …

Dynamic Response Of Poroelastic Materials Containing Bingham Fluid: Application To Electrorheological Fluids, Mete Kesan

Doctoral Dissertations

This work examines the dynamic response to harmonic loading of a disk of poroelastic material containing non-Newtonian Bingham fluid which exhibits a yield stress. Biot's poroelasticity equations and modified Darcy's law for non-Newtonian fluids exhibiting a yield stress are combined together to obtain the governing equations of the system for quasi-static case. Dissipation due to friction arising from the flow of fluid relative to the solid is taken into account but inertia effects are neglected. The response and the complex modulus of the system are calculated using the finite element method taking into account the nonlinear nature of Bingham fluid. …

Molecular Characterization Of A Cytotoxic Porin Protein From Campylobacter Jejuni And Its Role In Campylobacteriosis, David John Bacon

Doctoral Dissertations

Campylobacter jejuni is a major cause of enteritis in developed and developing countries. A cytotoxic complex was isolated from organism-free filtrates of broth grown organisms by screening for activity in HEp-2 cells following high performance liquid chromatography using a combination of size exclusion and DEAE column chromatography. The toxin was found to coincide with a 45 kDa protein possessing an N-terminus sequence indicative of a bacterial outer membrane porin protein together with a high molecular weight carbohydrate which was determined to be lipopolysaccharide (LPS).

The carbohydrate portion of the LPS had reactivity for the lectins Galanthus nivalis agglutinin, Maakia amurensis …

Perceived Versus Actual Attitude Similarity As Predictors Of Change In Interpersonal Attraction, Andrew Robert Mcgarva

Doctoral Dissertations

The present investigation was intended to identify factors that affect the degree to which interpersonal attraction changes over the course of face-to-face interaction. Participants completed a modified version of Byrne's (1971) attitude questionnaire, the Crowne-Marlowe Social Desirability Scale (1964), and Snyder's Self-Monitoring Scale and were then paired into attitudinally similar, dissimilar, or neutral dyads. Both before and after interacting for 40-minutes, dyads were asked to rate their interpersonal attraction toward their partner. Attitude similarity better predicted post-conversation interpersonal attraction when controlling for pre-conversation attraction than when not controlling for pre-conversation attraction. Social desirability, self-monitoring, and the coordination of vocal activity …

Contributions To The Theory Of Distance Functions And Its Application In General Topology, Lawrence Valery Neveu

Doctoral Dissertations

As non-Hausdorff spaces are becoming more important in topology, there is a need to consider new notions in topology to supplement the usual structures. This work uses distance functions to find useful generalizations (in a non-Hausdorff context) of the classes of spaces that are important in the Hausdorff setting. We begin, in the first part, with a historical overview that traces the evolution of the notion of distance and its role in the development of general topology.

In the second part of this work, we launch our study of distance functions. Using non-symmetric distance functions, called asymmetric, we generalize the …

The Multidimensionality Of Illusory Judgments: Reexamination Of Illusion Of Control Research, Paul Keith Presson

Doctoral Dissertations

The present dissertation examines the well-established research paradigm known as the illusion of control. Until now, researchers have employed one basic paradigm which has addressed the illusion of control as a unidimensional phenomenon. In Study 1, 91 female undergraduates were presented with three induction conditions used by previous researchers. Factor analyses showed that judgments from these tasks did not tap into a single process, but rather fell into two types of illusory judgments--belief- and contingency-based. In Study 2, 182 female undergraduates were exposed to the same three induction conditions used in Study 1 plus two additional contingency tasks. As in …

Beta-Carotene In The Bovine Corpus Luteum, Stephen Grimmell Judd

Doctoral Dissertations

There have been conflicting reports which associate a low dietary intake or plasma concentration of beta-carotene (BC) with decreased fertility in dairy cows. The bovine corpus luteum (CL), a transient endocrine gland formed subsequent to ovulation, produces the steroid hormone progesterone which sustains pregnancy and is associated with fertility. Because of its high concentrations of the antioxidant nutrient beta-carotene, the CL was examined to identify an in vivo function for BC, other than that as a precursor of retinol. Five non-lactating Jersey cows were fed a basal ration containing a low BC concentration. Each cow received either 0, 1.6, 8.0, …

The College President And The Technology Leader: Defining A New Role In Campus Planning, Elizabeth Ann Rivet

Doctoral Dissertations

The research investigated the working relationship between the small college president and the campus technology leader and determined some aspects that might facilitate and strengthen their relationship. The cross-sectional study considered, as voiced by the small college president, the extent of influence in campus wide decision making activities viewed as appropriate for the campus technology leader.

The research focused on presidents of small private and public accredited liberal arts schools in the United States, having between 500 and 3,000 full time students and offering (at least) baccalaureate degrees. The research instrument was a questionnaire containing thirty forced-choice questions which measured …

Quantified Sea Level History For The Middle Jurassic (Bajocian) Through Cretaceous (Santonian) Based On Russian Platform And Siberian Stratigraphic Data, Oleg Vladimir Pinous

Doctoral Dissertations

Quantified Eustatic Curve (QEC) for Bajocian (Mid Jurassic) through Santonian (Upper Cretaceous) was constructed on the basis of the stratigraphy of the Russian Platform. The Mesozoic tectonic stability of the central part of the Russian Platform provided a valid frame of reference upon which to base the eustatic curve. As such, this curve can be considered a reliable representation of eustasy. The stratigraphic hiatuses left by unconformities in the central part of the Russian Platform were filled with stratigraphic information from the more continuous stratigraphy of the subsiding regions such as Ryazan Saratov Trough and Northern Siberia. The curve makes …

Phylogenetic Diversity And Community Structure Of Sulfate-Reducing Bacteria In A Salt Marsh Sediment, Juliette Nicole Rooney Varga

Doctoral Dissertations

Phylogenetic diversity and community structure of sulfate-reducing bacteria (SRB) in a salt marsh sediment and rhizosphere of Spartina alterniflora were investigated. Uncultivated phylotypes were studied by selectively amplifying Desulfobacteriaceae 16S rRNA gene fragments from DNA extracted from salt marsh rhizosphere samples. An in vitro transcription technique was developed to synthesize reference RNAs containing sequences presumably identical to corresponding regions of the uncultivated organisms' 16S rRNAs. These reference RNAs were used in subsequent quantitative probing experiments. Oligonucleotide probes were designed to specifically target novel phylotypes and were tested for optimal hybridization wash conditions and target specificity. The newly designed probes were …

Pray Don't Tell Any Body That I Write Politics: Private Expressions And Public Admonitions In The Early Republic, Elisabeth Briggs Nichols

Doctoral Dissertations

This dissertation explores the intersection between personal letters and published admonitions during the decades following the American Revolution. Based on the analysis of letters and diaries composed between 1776 and 1830 by elite white women situated in the northeast, it reveals the extent to which correspondents appropriated, manipulated, or rejected the vocabulary and messages they discovered in novels, magazines, etiquette manuals, and social experts' pronouncements.

Uncertain about the cultural authority invested in the written word, correspondents self-consciously explored the meaning of writing as they composed their letters. As they wrote about writing, reading, the contrasts between rural and urban living, …

Absorption And Fluorescence Spectra Of Sodium In An Argon Matrix, Alan Bruce Tutein

Doctoral Dissertations

A computer simulation of the formation of trapping sites for sodium atoms trapped in a solid argon matrix has been performed, using experimentally determined argon-argon and sodium-argon potentials available in the literature. The simulation method is a greatly simplified version of the more time-consuming molecular dynamics approach. Optical absorption and emission spectra corresponding to the matrix-perturbed 3s-3p sodium transition were calculated for each simulated trapping site, using first-order perturbation theory and the available sodium-argon dimer potentials. Two of the three requisite sodium-argon dimer potentials, the X$\sp2\Sigma$ and the A$\sp2\Pi,$ have been determined experimentally, but for the B$\sp2\Sigma$ potential, only a …

Development And Application Of Molecular Techniques For The Detection Of Human Enteric Viruses In Environmental Samples, Patrick Michael Regan

Doctoral Dissertations

Shellfish and water have been implicated in the transmission of viral diseases. National surveillance data on waterborne and foodborne illnesses underestimate the public health significance of these viruses. The focus of this research was to evaluate, develop, and apply molecular techniques to detect human enteric viruses in environmental samples.

The initial study evaluated a nucleic acid hybridization assay using a $\sp{32}$P labeled cDNA probe to detect poliovirus in clams. Clams (Mercenaria mercenaria) were harvested from Narragansett Bay, Rhode Island. Poliovirus was detected in clams from the conditionally approved area in 3 of 9 collections and in the prohibited area in …

Student Interactions And Mathematics Discourse: A Study Of The Development Of Discussions In A Fifth-Grade Classroom, Sharon Marie Soucy Mccrone

Doctoral Dissertations

Mathematics reform efforts are gaining attention and support in the years since the dissemination of the National Council of Teachers of Mathematics (NCTM) Standards documents. Encouraging student interactions in small and large group settings, and promoting discussion and argumentation of mathematical ideas among students are two possible implications of the vision presented in the Standards. The goal of having mathematics discussions, however, can present a variety of classroom challenges. Many factors influence classroom discourse and need to be addressed in ways that inform teachers as they work toward creating a more interactive, discussion-based mathematics classroom.

The study examines the development …

Psychosocial And Sociostructural Determinants Of Mastery: The Context Of Age And Disability, Scott David Schieman

Doctoral Dissertations

The "active" and "potent" self has held a special interest to philosophers, psychologists, and sociologists since the inception of those disciplines. The present research uses sociological perspectives on social comparison and reference group theory to provide a framework for understanding the various dimensions of self-process in the context of age and disability. Specifically, this research examines associations between age, disability, and social status indicators as they impress upon personal agency or mastery.

This study uses secondary data that includes respondents aged 18 and over who resided in any of ten counties in Southwestern Ontario and were part of a two-wave …

Impact Of Land-Use And Climatic Changes On Hydrology Of The Himalayan Basin: A Case Study Of The Kosi Basin, Keshav Prasad Sharma

Doctoral Dissertations

Land-use and climatic changes are of major concern in the Himalayan region because of their potential impacts on a predominantly agriculture-based economy and a regional hydrology dominated by strong seasonality. Such concerns are not limited to any particular basin but exist throughout the region including the downstream plain areas. As a representative basin of the Himalayas, we studied the Kosi basin (54,000 km$\sp2)$ located in the mountainous area of the central Himalayan region. We analyzed climatic and hydrologic information to assess the impacts of existing and potential future land-use and climatic changes over the basin.

The assessment of anthropogenic inputs …

Adaptive Multiresolution Visualization Of Large Multidimensional Multivariate Scientific Datasets, Pak Chung Wong

Doctoral Dissertations

The sizes of today's scientific datasets range from megabytes to terabytes, making it impossible to directly browse the raw datasets visually. This presents significant challenges for visualization scientists who are interested in supporting these datasets. In this thesis, we present an adaptive data representation model which can be utilized with many of the commonly employed visualization techniques when dealing with large amounts of data. Our hierarchical design also alleviates the long standing visualization problem due to limited display space. The idea is based on using compactly supported orthogonal wavelets and additional downsizing techniques to generate a hierarchy of fine to …

Numerical Analysis For Blood Distribution In Complete Flow Cross-Section Microvascular Networks, Jewen Xiao

Doctoral Dissertations

As the blood flows through a bifurcation, the axisymmetric red blood cell concentration profile is skewed by plasma skimming. In the downstream segment of the bifurcation the concentration profile of red blood cells recovers symmetry by the red blood cell dispersion process.

In this study, the concentration convective equation, which models the red blood cell dispersion process, is solved with the method of finite differences in cylindrical coordinates. In the computation, a shear-induced diffusivity coefficient is used. The computed hematocrit ratios at the second bifurcation are compared with in vitro experimental data obtained from 50 $\mu$m serial trees with two …