Digital Commons Network^™

Structure Preserving Algorithms For Computing The Symplectic Singular Value Decom Position, Archara Chaiyakarn

Dissertations

In this thesis we develop two types of structure preserving Jacobi algorithms for com puting the symplectic singular value decomposition of real symplectic matrices and complex symplectic matrices. Unlike general purpose algorithms, these algorithms produce symplectic structure in all factors of the singular value decomposition.

Our first algorithm uses the relation between the singular value decomposition and the polar decomposition to reduce the problem of finding the symplectic singular value decomposition to th a t of calculating the structured spectral decomposition of a doubly structured m atrix. A Jacobi-like m ethod is developed to compute this doubly structured spectral decomposition. …

Stratification And Domination In Graphs And Digraphs, Ralucca M. Gera

Dissertations

In this thesis we combine the idea of stratification with the one of domination in graphs and digraphs, respectively.

A graph is 2-stratified if its vertex set is partitioned into two classes, where the vertices in one class are colored red and those in the other class are colored blue. Let F be a 2-stratified graph rooted at some blue vertex v . An F -coloring of a graph G is a red-blue coloring of the vertices of G in which every blue vertexu belongs to a copy of F rooted at u . The F -domination number γ …

Examining The Keyword Mnemonic Strategy As An Effective Academic Intervention For High School Students Labeled Emotional Or Behavioral Disordered, Karen A. Kleinheksel

Dissertations

This investigation explored whether keyword mnemonic strategies were effective for high school aged students labeled emotional or behavioral disordered(E/BD) in recalling the definitions of scientific vocabulary terms. Ten students labeled E/BD from a suburban public high school in a Midwestern state participated in this investigation. A demographic description of the subjects indicated the following information: (a) all students' ethnicities were Caucasian, (b) sixty percent of the subjects were male, (c) the average subject's age was 17 years 1 month, and (d) all students were in the tenth through twelfth grades.

In a multiple baseline across subjects design using a single …

Meaningful Learning: Reconciling The Tensions Between Constructivist And Environmentally Sustainable Pedagogy, Nancy Van Kannel-Ray

Dissertations

Critics of constructivism argue, in many ways correctly, that this approach to education is culturally and environmentally damaging because constructivism may not develop an understanding of the interdependence between the human community and the world in which people live. Advocates for environmentally sustainable pedagogy argue the importance of understanding patterns of thinking that allow communities to live sustainably. The purpose of this study is to resolve the tensions between the two pedagogical frameworks: constructivism and environmental sustainability.

The tensions are resolved in two ways. First, there are forms of constructivism that align in viable ways with the criteria critics argue …

Impact Of Standards On Physical Education Teacher Education: Curriculum, Collaboration, And Learning Outcomes, Xiangren Yi

Dissertations

Standards are sweeping across the physical education teacher education field. The purpose of this study was to investigate whether national standards had influenced a change of curriculum, and whether curriculum changes were related to standards, individual or institutional variables. The analysis will also identify whether there are any individual and institutional characteristics that are significant predictors for determining curriculum. This study's targeted participants are a random sample of 110 program directors working in institutions that have a Physical Education Teacher Education program.

Differences were found to exist in directors' perceptions regarding curriculum. Descriptive statistics and ANOVA analysis demonstrated the impact …

Hybrid Explicit-Implicit Fdtd-Fem Time-Domain Solver For Electromagnetic Problems, Kakhkhor Abdijalilov

Dissertations

The Finite-Difference Time-Domain (FDTD) method and Finite-Element (FEM) method are numerical techniques used for solving Maxwell's electromagnetic equations. FDTD-FEM hybrid methods opt for combining the advantages of both FDTD and FEM. In this dissertation, signal processing techniques were used to analyze the FDTD stability condition. A procedure, which reduces time-sampling error yet preserves the stability of algorithm is proposed. Both explicit and implicit time-stepping schemes were treated in the framework of the developed method. An improved version of the implicit-explicit FEM-FDTD hybrid method was developed. The new method minimizes reflection from the interface between different types of grids. A class …

Characteristics Of Nanocomposites And Semiconductor Heterostructure Wafers Using Thz Spectroscopy, Hakan Altan

Dissertations

All optical, THz-Time Domain Spectroscopic (THz-TDS) methods were employed towards determining the electrical characteristics of Single Walled Carbon Nanotubes, Ion Implanted Si nanoclusters and Si_1-xGe_x HFO₂, SiO₂ on p-type Si wafers.

For the nanoscale composite materials, Visible Pump/THz Probe spectroscopy measurements were performed after observing that the samples were not sensitive to the THz radiation alone. The results suggest that the photoexcited nanotubes exhibit localized transport due to Lorentz-type photo-induced localized states from 0.2 to 0.7THz. The THz transmission is modeled through the photoexcited layer with an effective dielectric constant described by a Drude …

Negotiation Of Software Requirements In An Asynchronous Collaborative Environment, Catherine Lowry Campbell

Dissertations

The effect of task structure and negotiation sequence on collaborative software requirements negotiation is investigated. This work began with an extensive literature review that focused on current research in collaborative software engineering and, in particular, on the negotiation of software requirements and the requisite collaboration for the development of such requirements. A formal detailed experiment was then conducted to evaluate the effects of negotiation sequence and task structure in an asynchronous group meeting environment. The experiment tested the impact of these structures on groups negotiating the requirements for an emergency response information system. The results reported here show that these …

Corrosion Studies On Alpha Tantalum And Beta Tantalum Coated Steel, Sung Min Maeng

Dissertations

Tantalum coating by sputtering, one form of physical vapor deposition (PVD), has been investigated as a replacement for chromium coatings on gun bores to protect them from erosion and corrosion due to its high ductility and high corrosion resistance in aggressive environments. When deposited as a film on steel substrates by sputtering, either α-Ta, β-Ta, or a mixture of both phases have been observed under varying deposition conditions. To evaluate corrosion behavior of Ta coatings, electrochemical impedance spectroscopy and potentiodynamic polarization were conducted as a function of coating thickness. The coating porosity was observed to decrease with increasing coating thickness …

Bus Arrival Time Prediction Using Stochastic Time Series And Markov Chains, Rajat Rajbhandari

Dissertations

Public transit agencies rely on disseminating accurate and reliable information to transit users to achieve higher service quality and attract more users. With the development of new technologies, the concept of providing users with reliable information about bus arrival times at bus stops has become increasingly attractive. Due to the fact that bus operation parameters and variables are highly stochastic, modeling prediction of bus travel and arrival times has become one of the many challenging tasks.

Stochastic time series and delay propagation models to predict bus arrival times using historical information were developed. Markov models were developed to predict propagation …

Characterizing The Evolution Of Operating Systems, Yi Peng

Dissertations

Examining the development and trends in software engineering technology is a huge undertaking. It is constantly evolving and affected by a large number of factors, which are themselves driven by a wide range of sub-factors. This dissertation is part of a long term project intended to analyze software engineering technology trends and how they evolve. This project is intended to analyze operating system trends and what are the factors that drive how they evolve. Basically, the following questions will be answered: "How to watch, predict, adapt to, and affect operating system's evolution trends?"

In previous research, YF Chen used statistical …

Computational Studies Of Viscoelastic Multiphase Flows, Shriram B. Pillapakkam

Dissertations

A finite element code based on the level set method is developed for performing two and three dimensional direct numerical simulations (DNS) of viscoelastic two-phase flow problems. The Oldroyd-B constitutive equation is used to model the viscoelastic liquid. The code is used to study transient and steady state shapes of Newtonian and viscoelastic drops in simple shear and buoyancy driven flows. The roles of the governing dimensionless parameters: Capillary number (Ca), Deborah Number (De) and the polymer concentration parameter c, in determining deformation of drops and bubbles, are also analyzed.

The numerical code permits us to vary Ca, De and …

Live, Virtual, And Constructive Environments For Performance Support, John Michael Lacontora

Dissertations

As military systems become more complex, the operation and support of these systems becomes intrinsically more difficult. The U.S. Army's current procurement process relies on industry to provide embedded training and performance support tools for the systems they produce. These tools are relatively new and in the early stages of development. As yet, they have failed to meet the needs of the technicians that are required to support these complex systems. Current efforts to provide enabling technologies that enhance the capabilities of automotive maintenance technicians are concentrated in three professional communities. First is the Performance Improvement community where work is …

Pattern Discovery In Structural Databases With Applications To Bioinformatics, Sen Zhang

Dissertations

Frequent structure mining (FSM) aims to discover and extract patterns frequently occurring in structural data such as trees and graphs. FSM finds many applications in bioinformatics, XML processing, Web log analysis, and so on. In this thesis, two new FSM techniques are proposed for finding patterns in unordered labeled trees. Such trees can be used to model evolutionary histories of different species, among others.

The first FSM technique finds cousin pairs in the trees. A cousin pair is a pair of nodes sharing the same parent, the same grandparent, or the same great-grandparent, etc. Given a tree T, our …

Tide-Influenced Contaminant Transport In Coastal Aquifers, Yong Peng

Dissertations

Coastal aquifers are distinguished from other aquifers because of tidal effects which cause complicated groundwater flow and contaminant transport phenomena in regions immediately adjacent to the coast. This study is designed to address the significance of tidal influence on contaminant transport by focusing on one-dimensional homogeneous coastal aquifers.

This study formulates a conceptual model and corresponding flow and transport equations, analyzes coastal boundary conditions, solves numerically the transport equation, and uses experiments to verify the numerical results.

Results of numerical and experimental studies conclude that tides can have a significant impact on contaminant transport, especially when under unconfined conditions, subject …

The Testing Of Semiconductor-Based Adsorption Modified Photosensitive Sensors For Their Response To A Volatile Organic Compound, Oxygen, Humidity, And Heating, Roberta Rosty

Dissertations

Two thin-film sensors, composed of different thicknesses (approximately 0.5 microns and 4.5 microns) of a cadmium sulfide layer coated with Rhodamine B fluorescent dye on a glass substrate, were tested for change in photoconductivity due to exposure to different concentrations of gaseous organic molecules in the parts-per-million (ppm) range.

It was theorized that the gaseous organic molecules would adsorb to the dyed semiconductor surface and that some energy would be transferred to the adsorbed analyte rather than to the cadmium sulfide semiconductor layer through the dye, thereby decreasing the photoconductivity of the surface in an amount proportional to the analyte …

Investigation Of Static And Dynamic Enhancement Of Laminar Natural Convection Cooling Of Electronics, Laurie Ann Florio

Dissertations

With the proliferation of consumer electronics devices and the increasingly demanding thermal control requirements for such devices, more effective and efficient means of cooling electronics are needed. The feasibility of three alternative approaches to enhancing pure natural convection cooling of electronics is investigated in the current research. The three static or dynamic methods investigated are alternate cross-flow passages, the strategic placement of transversely oscillating plates near the heat sources and a combined method using both the cross-flow passages and the strategically placed oscillating plates. These cooling methods are intended to operate in the regime for which natural convection cooling is …

Scattering Matrix Analysis Of Photonic Crystals, Valeriy Lukyanov

Dissertations

Using a scattering matrix approach we analyze and study the scattering and transmission of waves through a two-dimensional photonic crystal which consists of a periodic array of parallel rods with circular cross sections. Without making any assumptions about normal incidence, single mode propagation, and sufficient inter-scatter separation in the direction of propagation, we show how to compute the transmission and reflection coefficients of these periodic structures. The method is based on the computation of a generalized scattering matrix for one column of the periodic structure.

We also develop an analytical method to analyze and to study the scattering and transmission …

An Optic Fiber Sensor For Partial Discharge Acoustic Detection, Xiaodong Wang

Dissertations

Partial discharge (PD) is a very common problem in operating power transformers and is one of the factors that could lead to failure of power transformers, leading to power outage and expensive repairs. The acoustic wave induced by PD can be measured and used for monitoring, diagnosing, and locating potential failures in power transformers.

The effects of the temperature of the transformer and transformer oil are one of the very important parameters in PD and these effects are investigated in detail. The Fast Fourier Transform (FF1') is used to synthesize the measured data and results show that for periodic PD …

The Transition From High School To College : A Single-Case Study, Margaret R. Hay

Dissertations

Purpose. The purpose of this study was to use quantitative and qualitative data to describe the transition recent high-school graduates made to a small, rural community college. Both the students’ academic preparation and their own perceptions about their preparedness for college were described.

Method. Data from the transcripts of high-school graduates were examined using Chi square, tests of independent means, and analyses of variance to test the relationship to placement in developmental classes. The data included senior year course selections, the number of units taken in math, English, and textbook-dependent courses, and grade point averages in math, English, and textbook-dependent …

Intuitive Decision Making And Leadership Style Among Healthcare Executives In The United States, Cherie Whiting

Dissertations

The purpose of this two-phased, sequential, exploratory, mixed-methods study was to survey a sample of Fellows in the American College of Healthcare Executives in the United States and then interview selected individuals who scored in the highly intuitive category on the intuition survey to explore how they made intuitive decisions. In the first phase, quantitative research questions addressed the relationship between leadership style and the potential to make intuitive decisions, as well as the relationship and interaction between the potential to make intuitive decisions and age, gender, and size of company. In the second phase, qualitative interviews were used to …

A Critique Of The Urban Mission Of The Church In The Light Of An Emerging Postmodern Condition, Kleber De Oliveira Goncalves

Dissertations

The world is becoming an urban society. The urban expansion witnessed during the twentieth century and continuing into the twenty-first century is unprecedented in the history of the human civilization. Simultaneously, the Western world faces the paradigm shift from the modern era to a postmodern condition. Both movements have remarkable implications for the mission of the church in urbanized, postmodernizing societies. Shaped by the modern worldview, the church is now further ostracized by the postmodern condition.

While the literature of urban mission has grown in the past few years, very little consideration has been given to the particular issues and …

The Effect Of Embedded Metacognitive Prompts And Probes On Students’ Awareness In A Multimedia Lesson For Elementary School Students, Wendy Janine Parcel Edd

Dissertations

In a study he called The Effect of Embedded Metacognitive Cues and Probes on Use of Learner Control Features in an On-line Lesson for Elementary Students, Watson (2001) found that minimal prompting by an online tutorial increased 5th grade students’ comprehension of how much they understood. While Watson’s findings demonstrated a significant difference in the ability of prompted and non-prompted students to accurately predict their own performance on posttests, actual scores were not greater than those of control students until the results were analyzed by gender. The purpose of this study was to replicate and extend Watson’s study to determine …

Job Satisfaction And Its Relationship To Organizational And Religious Commitment Among Workers At Northern Caribbean University, Donna Brown

Dissertations

Problem. Recruiting teachers and motivating them to stay in their jobs present a challenge to educational institutions in Jamaica. Given the importance of workers' satisfaction to the health of an organization and the link between job satisfactionand turnover rate, then an examination of job satisfaction at Northern Caribbean University (NCU) is a priority. Based on this background, the primary focus of this study was to investigate job satisfaction and its relationship to organizational and religious commitment among workers at NCU.

Method. This study utilized a quantitative, descriptive research design. A survey questionnaire was sent to all full-time administrators …

A Descriptive Examination Of Protective Factors: Analysis Of Male Completers Of An Alternative Educational Program, Rona Dominique Roberts

Dissertations

A growing number of students, primarily at the high school level, are being assigned to alternative education programs for behavior management. These students, who engage in risky behaviors, may also come from high-risk environments, suggesting a possible correlation between these two factors that may increase the likelihood of unsuccessful life outcomes. Very little research has been conducted to determine the effectiveness of these programs after completion; however, because of the increasing prevalence of alternative education programs across the nation, questions have emerged as to whether or not students assigned to these programs will continue to engage in at-risk behaviors after …

The Glacial Geology Of Southern St. Joseph County, Michigan, Linda Nicks

Dissertations

The objective of the dissertation was to map the glacial geology in southern St. Joseph County, Michigan. The surficial geology was divided into three distinct land systems which are moraine, outwash and fan deposits. The Sturgis Moraine is the most prominent feature transecting the study area from east to west. The topography is further dissected by southwest-trending channels interpreted as tunnel channels.

Thick accumulations of sand and gravel in the study area indicate that glacial meltwater deposition played a dominant role in shaping the landscape. Based on the relative size of the channels and outwash deposits, the largest contribution from …

Origin Of The Central Kalamazoo River Valley, Southwestern Michigan, Usa, Andrew Kozlowski

Dissertations

Chapter I

Introduction

Southern Michigan's geomorphology is a testament to the glacial processes that buried and sculpted the landscape during the last glaciation. Many glacial landforms in southwestern Michigan, including the Kalamazoo River Valley, provide evidence that aids in understanding the chronology, ice dynamics and glacial processes that occurred in Michigan during the last ice age.

As the climate began to warm about 20,000 yr B.P. (Larson and Schaetzl, 2001) the extensive Laurentide Ice Sheet began to recede from its maximum southern position reached during the Late Wisconsinan (Figure 1). It was at this point that modem surficial drainage systems …

Interferences In Electron Emission Spectra For H+ Impact On H2, Sabbir Hossain

Dissertations

No abstract provided.

Investment And Capital Flows Under Uncertainty And Capital Market Imperfection In Oil Producing Countries, Mohamed Gaber Hassan Elsayed

Dissertations

This dissertation analyzes and estimates the interactions between domestic investment and each type of capital flow under uncertainty and capital market imperfection in 13 oil-producing countries from 1981 to 2003. First, we discuss the recent development in investment theories under uncertainty, irreversibility, and imperfect capital market. Secondly, decomposing uncertainty into permanent and transitory components--based on C-GARCH--we constructuncertainty measures of broad macroeconomic variables in addition to oil price.

Thirdly, a model of four simultaneous equations is developed to capture dynamic interactions. My contribution is twofold. First, not only do we consider the impact of uncertainty and credit market imperfection on investment, …

Phase Coherent Effects In The Speckle Correlation Of Light Scattered From Volume Disordered Media And Randomly Rough Surfaces, Bogdan Danila

Dissertations

We present a study of the statistics of the intensity patterns produced when coherent light is scattered by random media (volume disorder) or randomly rough surfaces. Such a random, granular interference pattern is called speckle. Particular emphasis is on the statistical correlations arising between thefluctuations of the intensities corresponding to distinct scattering paths; which are quantified by the speckle correlation function. In the first part, we present results for the correlation function computed for volume-disordered media by means of numerical simulation. Our focus is on the sensitivity of the correlationfunction to statistical parameters characterizing the volume distribution of the refraction …