Digital Commons Network^™

Cloud Computing:Strategies For Cloud Computing Adoption, Faith Shimba

Dissertations

The advent of cloud computing in recent years has sparked an interest from different organisations, institutions and users to take advantage of web applications. This is a result of the new economic model for the Information Technology (IT) department that cloud computing promises. The model promises a shift from an organisation required to invest heavily for limited IT resources that are internally managed, to a model where the organisation can buy or rent resources that are managed by a cloud provider, and pay per use. Cloud computing also promises scalability of resources and on-demand availability of resources.

Although, the adoption …

Natural Selection On Mrna Secondary Structure And Its Correlation With Protein Functional Groups, Suresh Solaimuthu

Dissertations

Natural selection may occur at multiple levels of the biological hierarchy, including at the molecular level. It may occur on any phenotypic trait that evidences variation and that is heritable. This research uses computational methods to investigate whether the stability of the secondary structures of mRNAs has been the subject of natural selection.

The DNA sequence that codes for a particular target protein is only partially determined by that protein, since the redundancy of the genetic code permits multiple possible synonymous codons for each peptide. An RNA transcript of a DNA protein template (gene) folds back on itself through complementary …

Design Of Novel Drug Delivery System And Optimal Dosage Regimens, Kwang Seok Kim

Dissertations

Three representative drug delivery systems were analyzed to emphasize the roles of mathematical models and computer-aided simulations in pharmaceutical research. In the first project, a protocol was developed so that the optimal regimen, consisting of the intravenous boluses and subsequent infusion of theophylline, could be obtained once information on the pharmacokinetics became available. The method was based on a two-compartment model of the human body. A module was created and posted on a website for free access. The second project dealt with the transdermal heat-assisted delivery of corticosterone. Heat conduction and drug diffusion through the patch and the skin were …

Study Of Magnetic Helicity In Solar Active Regions And Its Relationship With Solar Eruptions, Sung-Hong Park

Dissertations

It is generally believed that eruptive phenomena in the solar atmosphere such as solar flares and coronal mass ejections (CMEs) occur in solar active regions with complex magnetic structures. The magnetic complexity is quantified in terms of twists, kinks, and interlinkages of magnetic field lines. Magnetic helicity has been recognized as a useful measure for these properties of a given magnetic field system. Magnetic helicity studies have been naturally directed to the energy buildup and instability leading to solar eruptions. However, in spite of many years of study, detailed aspects of initiation mechanisms of eruptive events are still not well …

A Numerical Study On The Propagation And Interaction Of Strongly Nonlinear Solitary Waves, Qiyi Zhou

Dissertations

We study numerically a strongly nonlinear long wave model for surface gravity waves propagating in both one and two horizontal dimensions. This model often referred to as the Su-Gardner or Green-Naghdi equations can be derived from the Euler equations under the assumption that the ratio between the characteristic wavelength and water depth is small, but no assumption on the wave amplitude is required. We first generalize the model to describe large amplitude one-dimensional solitary waves in the presence of background shear of constant vorticity. After computing the solitary wave solution of the strongly nonlinear model, the interaction between two solitary …

Computational Methods For Two-Phase Flow With Soluble Surfactant, Kuan Xu

Dissertations

A mathematical model is formulated and solved for the two-phase flow of a viscous drop or inviscid bubble in an immiscible, viscous surrounding fluid in the zero Reynold's number or Stokes flow limit. A surfactant that is present on the interface is also soluble in the exterior fluid, and the drop is deformed by an imposed linear flow. The geometry is two-dimensional and Cartesian.

The dissolved surfactant is considered in the physically realistic limit of large bulk Péclet number. That is, it convects and diffuses as a passive scalar in the bulk flow where the ratio of its convection to …

Atomic And Electronic Structure Studies Of Nano-Structured Systems : Carbon And Related Materials, Sumit Saxena

Dissertations

Modeling in the framework of density functional theory has been conducted on carbon nanotubes and graphene nano-structures. The results have been extended to non-carbon systems such as boron nanostructures. Computational studies are complemented by experimental methods to refine the structural models and obtain a better understanding of the electronic structure.

It is observed that the zigzag edged bilayered graphene nanoribbons are highly unstable as compared to their armchair counterparts. A novel approach has been proposed for the patterning of chirality/diameter controlled single walled carbon nanotubes. Nanotube formation is found to be assisted by edge ripples along with the intrinsic edge …

The Public Understanding Of Climate Change : A Case Study Of Taiwanese Youth, Shih-Yun Kuo

Dissertations

Global climate change is likely to be the most challenging environmental dilemma of the 21st century because its impacts on ecosystems and human society are transnational in scale and long term in scope. Due to its high scientific complexity and uncertainty and high political and economic sensitivity, mitigating the problem will require interdisciplinary cooperation and collective and sustained efforts on the part of all nations. Sufficient domestic support from both government and the lay public will not only be significant to the success of an international climate regime, but also crucial to the effectiveness of potential domestic climate policies.

Such …

Comparing Perceptions Of Campus Crime Severity Among Community College And Public Four-Year University Students, Loren Morell Lundstrom

Dissertations

In recent years violent crimes on several university campuses have been highlighted by mass media, drawing national attention to the issue of campus crime. Not all college campuses, however, experience the same level of crime. While community colleges serve roughly half of all undergraduates in the U.S., statistically these public institutions account for a much lower percentage of violent crimes than their public four-year university counterparts. With the thought that perceptions and beliefs govern one’s behavior, this study considers the possibility that elements of institutional culture influence student perceptions about campus crime. Two hundred and sixty-five (265) college students, from …

Urban Middle School Teachers: Tenured Versus Non-Tenured Teachers And The Impact They Have On Academic Achievement, Rochelle Harris-Clark

Dissertations

The Iowa Test of Basic Skills (ITBS) is used in the district of Study School No. 1 to give insight on student academic skill level in terms of years and months. Teacher strategies and expertise in the area of education is an integral part of the educational process. Tenure status, or the years of experience, is plagued with the idea that it promotes or has an impact on student achievement. Although there were a significant number of tenured special education and general education teachers at the study school during the 2005–2006, 2006–2007, and 2007–2008 school years, the school did not …

An Automated Framework For Defect Detection In Concrete Bridge Decks Using Fractals And Independent Component Analysis, Fadi Abu-Amara

Dissertations

Bridge decks deteriorate over time as a result of deicing salts, freezing-andthawing, and heavy use, resulting in internal defects. According to a 2006 study by the American Society of Civil Engineers, 29% of bridges in the United States are considered structurally deficient or functionally obsolete. Ground penetrating radar (GPR) is a promising non-destructive evaluation technique for assessing subsurface conditions of bridge decks. However, the analysis of GPR scans is typically done manually, where the accuracy of the detection process depends on the technician's trained eye. In this work, a framework is developed to automate the detection, localization, and characterization of …

Local Radial Basis Function Methods For Solving Partial Differential Equations, Guangming Yao

Dissertations

Meshless methods are relatively new numerical methods which have gained popularity in computational and engineering sciences during the last two decades. This dissertation develops two new localized meshless methods for solving a variety partial differential equations.

Recently, some localized meshless methods have been introduced in order to handle large-scale problems, or to avoid ill-conditioned problems involving global radial basis function approximations. This dissertation explains two new localized meshelss methods, each derived from the global Method of Approximate Particular Solutions (MAPS). One method, the Localized Method of Approximate Particular Solutions (LMAPS), is used for elliptic and parabolic partial differential equations (PDEs) …

Criterion-Referenced Assessment Literacy Of Educators, James David King

Dissertations

This study investigated the assessment literacy of educators in regard to criterion-referenced tests. For the purpose of this study, administrators included principals and assistant principals within a school. First, the study determined the degree of training in measurement, assessment, and statistics that educators have received. Second, the study investigated the assessment knowledge of educators based on their performance on the Criterion-Referenced Questionnaire. Third, the study investigated if years experience, type of certification, or highest degree held had a significant difference on their performance on the Criterion-Referenced Questionnaire. Fourth, the study investigated educators’ attitudes toward the use of measurement, assessment, and …

Isotropic And Anisotropic Metallic And Bimetallic Nanoparticles And Their Potential Applications In Biology, Minghong Liu

Dissertations

The development of synthetic procedures that produce nanoscale materials with controlled morphology is a significant area of investigation in nanotechnology. We have developed new synthetic procedures for fabrication of isotropic and/or anisotropic nanomaterials composed of palladium, ruthenium, nickel and alloys of palladium-ruthenium. The nanomaterials were fully characterized and were found to display unique size dependent properties. The electrochemical properties of isotropic palladium, ruthenium and palladium-ruthenium nanoparticles were investigated and the results showed that the particles were capable of charge storage and charge transfer on demand. Anisotropic palladium, ruthenium and palladium ruthenium nanoparticles were also fabricated and fully characterized. The nanoparticles …

The Scholarly Activity Predictor Model Among Counseling Psychology Doctoral Students: A Modification And Extension, Daniel M. Huber

Dissertations

The purpose of the current study was to help understand scholarly activity better among counseling psychology doctoral students. Two new variables were added to the previously created predictor model of scholarly activity: advisory working alliance and research competence. Three path analytic models were designed in the current study: (1) a primary hypothesized model, (2) an alternative model, and (3) a trimmed model. In the first model, grounded in social-cognitive career theory (SCCT) and the research training environment (RTE) theory, scholarly activity was hypothesized to be explained directly by research interests, research outcome expectations, research self-efficacy, research competence, and year in …

Gold Nanoparticle - Modified Zinc Oxide Nanoparticles As Novel Photocatalytic Materials, Nayane Udawatte

Dissertations

The current study entails the construction of a novel nano-composite catalyst based on ZnO and Au nanoparticles and demonstrates its distinctive photocatalytic characteristics. Monodisperse gold nanoparticles (GNPs) passivated with monolayers of tiopronin or glutathione were synthesized via facile methods, and they were assembled on ZnO nanoparticles to form the nanocatalyst.

Steady state and time resolved photoluminescent studies on the nanocomposite revealed interesting charge transfer characteristics within the nanocomposite. Enhanced photooxidation of rhodamine 6G was observed for the nano-composite over bare ZnO, and modulation of photoactivity with the extent of GNP loading was illustrated. Photoreduction of thionine over the nanocomposite was …

Studies Of Meson Mass Spectra In The Context Of Quark-Antiquark Bound States, Mallika Dhar

Dissertations

This dissertation deals with the computation of meson mass spectra in the context of quarkantiquark (q ¯ q) bound-state. Traditionally the q ¯ q bound-state problem is treated by solving the non-relativistic Schrödinger equation in position representation with a linear confining potential and a Coulomb-like attractive potential. For high energy, relativistic kinematics is necessary. It is well known that relativistic kinematics cannot be treated properly in position representation, but it can easily be handled in momentum representation. On the other hand, the linear potential and Coulomb-like potential have singularities in momentum-space and complicated subtraction procedure is necessary to treat the …

Pattern Recognition For Fault Detection, Classification, And Localization In Electrical Power Systems, Qais Hashim Alsafasfeh

Dissertations

The longer it takes to identify and repair a fault, the more damage may result in the electrical power system, especially in periods of peak loads, which could lead to the collapse of the system, causing the power outage to extend for a longer period and larger parts of the electrical network. Reducing the outage time and immediate restoration of service can be achieved if the fault type and location are determined in a timely and precise manner.

An integrated algorithm that is based on generating unique signatures from the electric current signal to detect, classify, and localize a fault …

Synthesis And Characterization Of Monolayer Protected Gold Nanoparticles And A Gold-Titanium Dioxide Nanocomposite Intended For Photocatalytic Degradation Of Environmental Pollutants, Piyadarsha Amaratunga

Dissertations

Semiconductor and metal clusters in the nanometer size regime display interesting optical, electronic and chemical properties that are size dependant. Highly monodisperse gold nanoparticles of different sizes have been synthesized and isolated by newly developed methodologies, using tiopronin as the capping ligand. Titanium dioxide nanoparticles (Ti0₂) have been used as the photocatalytic center and gold nanoparticles have been attached on Ti0₂ to make a nanocomposite. According to the findings, gold nanoparticles play a vital role in enhancing the photocatalytic activity of Ti0₂, by facilitating the charge separation. Further, the photocatalytic activity also can be tuned …

Assessing Problem Solving Strategy Differences Within Online And Face-To-Face Courses And Their Relationship To Pre-Service Teachers' Competence And Confidence For Integrating Technology Into Teaching, Sharon L. Peterson

Dissertations

This quantitative research study identifies the problem solving strategies preservice teachers use in learning specific technology skills within an educational technology methods class which is offered both online and face to face. It also examines how such strategies differ by the format of this course, and to what extent these strategies and/or course format correlate with the students' expressed level of confidence and competence to integrate technology into their future classroom settings. The study utilizes data extracted from surveys of over 1,500 students who had taken the educational technology methods course via online or face-to-face format during one of nineteen …

Structure-Property Correlation In Cyclopolymerization Of New Acrylate-Based Functional Monomers, Huseyin Tas

Dissertations

New ether dimer; (ED-Od) and (ED-Eh) and diester; (ODE) and (EHDE) derivatives of α-(hydroxymethyl)acrylate, each having two octadecyl and 2-ethylhexyl side chains respectively, and an amine-linked di(2-ethylhexyl)acrylate (AL-Eh), having three 2-ethylhexyl side chains, were synthesized and (co)polymerized to evaluate the effects of differences in the structures of the monomers on final (co)polymer properties, particularly glass transition temperature, Tg. The free radical polymerizations of these monomers yielded high molecular weight polymers. Cyclopolymer formation of ED-Od, ED-Eh and AL-Eh was confirmed by 13C NMR analysis and the cyclization efficiencies were found to be very high (~100%). Copolymers of ED-Od, ODE, ED-Eh, EHDE, …

Design, Synthesis, And Polymerization Of Novel Heterocyclic Monomers As Precursors For Functional Polyester, Poly(Ester Amide)S And Polyamides, Eylem Tarkin-Tas

Dissertations

The research presented in this dissertation involves the synthesis and polymerization of heterocyclic monomers which pave the way to biodegradable polyester nanocomposites, functional polyesters or poly(ester amide)s, functional polyamides and supramolecular polymers. The key monomers are ε-caprolactone, γ-acetamido-ε- caprolactone, γ-ethylene ketal-ε-caprolactam and α-amino-ε-caprolactam.

Poly(ε-caprolactone) organo-modified montmorillonite nanocomposites were prepared by in-situ polymerization using dibutyltin dimethoxide as initiator/catalyst. The montmorillonite was first modified with 1-decyl-2-methyl-3-(11-hydroxyundecyl)- imidazolium cation. The hydroxyl functionality was used for not only initiating polymer chains from the surface of the clay platelets but also for grafting polymer chains to the surface by acting as a reversible chain transfer …

Dnagents: Genetically Engineered Intelligent Mobile Agents, Jeremy Otho Kackley

Dissertations

Mobile agents are a useful paradigm for network coding providing many advantages and disadvantages. Unfortunately, widespread adoption of mobile agents has been hampered by the disadvantages, which could be said to outweigh the advantages. There is a variety of ongoing work to address these issues, and this is discussed. Ultimately, genetic algorithms are selected as the most interesting potential avenue. Genetic algorithms have many potential benefits for mobile agents. The primary benefit is the potential for agents to become even more adaptive to situational changes in the environment and/or emergent security risks. There are secondary benefits such as the natural …

Differentiating Classes From Dimensions Under Unfavorable Data Conditions: Monte Carlo Comparisons Of Taxometric And Latent Variable Mixture Models, Anthony Olufemi Ahmed

Dissertations

Taxometric and latent variable mixture models can aid in (1) determining whether the source of population heterogeneity, a latent variable, θ, is best explain by a dimensional (one-class) or taxonic (two-class) model and (2) distinguishing between constructs continuously distributed and those that are Bernoulli distributed at the latent level. Although these models have gained widespread use in psychology research, few have been systematically evaluated to determine the robustness of their results when statistical assumptions are violated (e.g., severe skew, unequal mixing proportions, etc.). The current study examined the performance of Meehl’s taxometric procedures and two latent variable mixture models: a …

Urban Middle School General Education: Tenured Versus Non-Tenured Teachers And The Impact On Academic Achievement, Trenese Nicole Dancy

Dissertations

The Iowa Test of Basic Skills (ITBS) is used in the Cahokia Unit School District No. 187 to give insight on student academic skill level in terms of years and months. Teacher strategies and expertise in the area of education is an integral part of the educational process. Tenure status, or the years of experience, is plagued with the idea that it promotes or has an impact on student achievement. In this study the researchers wanted to determine if there was a significant relationship between teacher tenure status (independent variable) and student academic achievement (dependent variable). Preand post-ITBS reading and …

Principals' Perceptions Of Distributed Leadership In An Elementary School Setting, David Dwain Eggen

Dissertations

No abstract provided.

Urban Middle School Instructional Special Education: Tenured Versus Non-Tenured Teachers And The Impact On Academic Achievement, Sheryl Marie Wilson

Dissertations

The Iowa Test of Basic Skills (ITBS) is used in the Cahokia Unit School District No. 187 to give insight on student academic skill level in terms of years and months. Teacher strategies and expertise in the area of education are an integral part of the educational process. Tenure status, or the years of teaching experience, is plagued with the idea that it promotes or has an impact on student achievement. The purpose of this study was to examine if students receiving instruction from non-tenured special education teachers demonstrate the same gains in the areas of reading and math as …

Relativistic Studies Of The Charmonium And Bottomonium Systems Using The Sucher Equation, Charles Martin Werneth

Dissertations

In this dissertation, bound states of quarks and anti-quarks (mesons) are studied with a relativistic equation known as the Sucher equation. Prior to the work in this dissertation, the Sucher equation had never been used for meson mass spectra. Furthermore, a full angular momentum analysis of the Sucher equation has never been studied. The Sucher equation is a relativistic equation with positive energy projectors imposed on the interaction. Since spin is inherent to the equation, the Sucher equation is equivalent to a relativistic Schrödinger equation with a spin-dependent effective potential. Through a complete general angular momentum analysis of the equation, …

Individual-Based Modeling Of White-Tailed Deer (Odocoileus Virginianus) Movements And Epizootiology, Lene Jung Kjaer

Dissertations

White-tailed deer (Odocoileus virginianus) are important game mammals and potential reservoirs of diseases of domestic livestock, so diseases of deer are of great concern to wildlife managers. In many situations, models can be useful for integrating existing data, understanding disease transmission patterns, and predicting effects on host populations. Individual-based modeling (IBM) has become more commonplace in ecology as a tool to link individual behavior to population dynamics and community interactions, especially for gauging the effects of management actions. Spatially explicit IBMs are especially useful when ecological processes, such as disease transmission, are affected by the spatial composition of the environment. …

Inhibition Studies Of Serine Hydrolases By Cyclic Phosphates And Phosphonates, Supratik Dutta

Dissertations

The serine hydrolase superfamily is one of the largest known enzyme families comprising approximately 1% of the predicted protein product in human genome. This family of enzymes contains a catalytic triad that is mainly consists of serine, aspartic acid/glutamic acid and histidine residues in their active sites. It has been proposed that the potential drug targets for Alzheimer’s disease and diabetes type 2 are enzymes that belong to this enzyme family. Acetylcholinesterase is an enzyme that catalyses the breakdown of acetylcholine, a neurotransmitter that helps transport information from one nerve cell to another. Breakdown of acetylcholine in Alzheimer’s disease patients …