Digital Commons Network^™

Improvement Of Eeg Based Brain Computer Interface By Application Of Tripolar Electrodes And Independent Component Analysis, Hongbao Cao

Doctoral Dissertations

For persons with severe disabilities, a brain computer interface (BCI) may be a viable means of communication, with scalp-recorded electroencephalogram (EEG) being the most common signal employed in the operation of a BCI. Various electrode configurations can be used for EEG recording, one of which was a set of concentric rings that was referred to as a Laplacian electrode. It has been shown that Lapalacian EEG could improve classification in EEG recognition, but the complete advantages of this configuration have not been established.

This project included two parts. First, a modeling study was performed using Independent Component Analysis (ICA) to …

Micro-, Nano-Integrated Composites Based On Cellulose Microfibers, Qi Xing

Doctoral Dissertations

No abstract provided.

An Empirical Examination Of The Effects Of Ethics, Disclosure, And Signal Theory On Disciplinary Actions Within The Accounting Profession, Benjamin Mcmillan

Doctoral Dissertations

There has been extensive research examining the relationship between the public mission of the accounting profession and the private interests of its professionals. All professions have been offered a special place within society due to the importance of the functions they perform as well as their stated public missions. In exchange, society delegates specific rights to the professions such as exclusivity of practice, self-discipline, and self-selection of their membership. Existing research suggests that the accounting profession's private interests have potentially encroached upon its public mission.

By using the Economic Theory of the Self Regulated Profession, Disclosure Theory, and Signal Theory, …

Radiation Detectors And Sources Enhanced With Micro/Nanotechnology, Chad Michael Whitney

Doctoral Dissertations

The ongoing threat of nuclear terrorism presents major challenges to maintaining national security. Currently, only a small percentage of the cargo containers that enter America are searched for fissionable bomb making materials. This work reports on a multi-channel radiation detection platform enabled with nanoparticles that is capable of detecting and discriminating all types of radiation emitted from fissionable bomb making materials. Typical Geiger counters are limited to detecting only beta and gamma radiation. The micro-Geiger counter reported here detects all species of radiation including beta particles, gamma/X-rays, alpha particles, and neutrons. The multi-species detecting micro-Geiger counter contains a hermetically sealed …

Micro, Nano Encapsulation Methods For Sustained Release Drug Formulations And Biomimetic Applications, Shantanu Balkundi

Doctoral Dissertations

The Layer-by-Layer (LbL) assembly technique was used to obtain a new type of protein/polyphenol microcapsule based on naturally occurring polyphenol (-)-epigallocatechin gallate (EGCG) and gelatin, type A. The dependence of permeability on the molecular weight of permeating substances was studied and compared with commonly used polyallylamine/polystyrene sulfonate capsules. A quartz crystal microbalance was used to monitor the regularities of EGCG adsorption in alternation with type A and B Gelatins and electrophoretic mobility measurements were used that indicated that the nature of assembly was dependent on Gelatin properties. It was shown that EGCG retains its antioxidant activity in the LbL assemblies. …

Applications Of Electricity In The Rehabilitation And Health Monitoring Of Concrete Structures, Saiprasad Vaidya

Doctoral Dissertations

The dissertation research work presented herein consists of two separate findings: one investigates a potential new coating technique that could be used to rehabilitate deteriorated concrete sewer pipes, and the other researches inducing electrical conductivity into geopolymer concrete to serve as smart material by being able to sense stress changes. Both applications utilize electricity to enhance the performance and/or functionality of hardened cementitious materials.

Microbiologically induced corrosion (MIC) in concrete wastewater conveyance systems is a leading deterioration mechanism in such structures. This work focuses on breaking the MIC cycle by preventing colonization of the bacteria responsible for converting hydrogen sulfide …

Applied Electrokinetics For Tissue Engineering Applications, Stephanie R. Tully-Dartez

Doctoral Dissertations

Tissue engineering could provide an alternative source of transplant tissue regardless of donor supply and with reduced risk of immune rejection. Engineered tissue requires three critical components for successful development: the cells, growth factors, and the scaffold on which they will initially grow. The scaffold acts as a temporary extracellular matrix (ECM) allowing cell attachment and acclimation to the environment prior to synthesis and construction of the cell's native ECM. Prior to cell seeding, the scaffold must be characterized to determine whether or not the pore geometry is conducive to cell implantation. Electrochemical impedance spectroscopy (EIS) provides a unique and …

Text Summarization Using Concept Hierarchy, Xiaomei Huang

Doctoral Dissertations

This dissertation aims to create new sentences to summarize text documents. In addition to generating new sentences, this project also generates new concepts and extracts key sentences to summarize documents. This project is the first research work that can generate new key concepts and can create new sentences to summarize documents.

Automatic document summarization is the process of creating a condensed version of the document. The condensed version extracts the key contents from the original document. Most related research uses statistical methods that generate a summary based on word distribution in the document. In this dissertation, we create a summary …

Computational Simulation Of Strain Localization: From Theory To Implementation, Shouxin Wu

Doctoral Dissertations

Strain localization in the form of shear bands or slip surfaces has widely been observed in most engineering materials, such as metals, concrete, rocks, and soils. Concurrent with the appearance of localized deformation is the loss of overall load-carrying capacity of the material body. Because the deformation localization is an important precursor of material failure, computational modeling of the onset and growth of the localization is indispensable for the understanding of the complete mechanical response and post-peak behavior of materials and structures. Simulation results can also be used to judge the failure mechanisms of materials and structures so that the …

Nano-Formulation And Controlled Delivery Of Low Solubility Anticancer Drugs, Anshul Agarwal

Doctoral Dissertations

Optimal drug delivery and reduction of systemic adverse effects have been age old problems in chemotherapeutics in all types of human cancer. During chemotherapy, using water insoluble drugs like paclitaxel and tamoxifen, it has been realized that better formulations are needed for more specific and controlled drug delivery of these agents. In a novel approach to form high content stable nanocolloids of these drugs with controllable release rate, a sonicated layer-by-layer (LbL) polyelectrolyte coating technology is suggested. The desired features of pharmaceutical carriers for intravenous administration include their small size and biodegradability, good loading capacity for a given drug, high …

Single-Walled Carbon Nanotube Device Fabrication Using Spin Coating Of Dispersions, Paul Jeremy Hummel

Doctoral Dissertations

This research looks at ways to utilize already synthesized carbon nanotubes (CNT) to manufacture electrical connections using current tools and fabrication methods employed in the semiconductor industry. Purchased single-walled carbon nanotubes (SWNT) are separated and placed in suspension using poly(sodium styrene sulfonate) (PSS). The PSS non-covalently bonds to the SWNTs, causing them to repel each other due to the negative charge of the PSS. The suspension of SWNTs is spin coated over a processed silicon (Si) wafer with fabricated trenches. A Si wafer with a top silicon dioxide (SiO 2) layer is spin coated with Shipley 1827 photoresist. UV light …

Discrete Nondeterministic Modeling Of Biochemical Networks, John R. Jack

Doctoral Dissertations

The ideas expressed in this work pertain to biochemical modeling. We explore our technique, the Nondeterministic Waiting Time algorithm, for modeling molecular signaling cascades. The algorithm is presented with pseudocode along with an explanation of its implementation. The entire source code can be found in the Appendices. This algorithm builds on earlier work from the lab of Dr. Andrei Nun, the advisor for this dissertation. We discuss several important extensions including: (i) a heap with special maintenance functions for sorting reaction waiting times, (ii) a nondeterministic component for handling reaction competition, and (iii) a memory enhancement allowing slower reactions to …

A Theoretical Study Of Methanol Oxidation Mechanisms By Methanol Dehydrogenase Enzymes For Fuel Cell Applications, Nagesh B. Idupulapati

Doctoral Dissertations

Enzymes are considered for electrochemical generation of power in fuel cells. Methanol dehydrogenase (MDH) is one such enzyme, which has been used as an anodic catalyst for a methanol-fed biofuel cell producing enough power for small electronic device applications. In practice, however, there are power output limitations associated with this MDH fuel cell, which may potentially be eliminated or reduced if the reactivity of this enzyme during the oxidation of methanol at the molecular level is clearly understood.

Two mechanisms for the methanol oxidation process by MDH have been proposed in the literature, Addition-Elimination (A-E) and Hydride Transfer (H-T), but …

The Relationship Between Pedagogical Content Knowledge And Mathematics Teacher Questioning Strategies, Lynne Smith Nielsen

Doctoral Dissertations

The purpose of this study was to determine whether an intense two-week professional development program for middle school mathematics teachers, along with follow-up classroom visits, video review of lessons (with feedback), and two six-hour follow-up sessions each semester would improve teacher questioning strategies and promote higher-level questioning based on Bloom's (1956) Taxonomy of cognitive categories. A second purpose of the study was to determine whether, through reflection and instructor feedback, teachers would gain the ability to involve students in high press questioning situations. The third purpose of the study was to investigate whether relevant professional development would result in an …

Chasing Μ, Joseph P. Cannon

Doctoral Dissertations

Conducting and semiconducting, π-conjugated polymers are promising materials for micro- and nano-optoelectronic applications because of their widely tunable physical, electrical, and optical properties. These polymers have been used to fabricate a number of electronic devices including field-effect transistors, light-emitting diodes, and photovoltaic cells. However, widespread commercial application of these devices has yet to be realized, due in part to poor electronic transport characteristics and device degradation.

Nanostructuring of conjugated polymers by various methods has demonstrated marked improvements in molecular ordering and electronic transport. In this research, nanoscale, tubular structures of semiconducting polymers fabricated by template wetting nanofabrication procedures are explored. …

The Impact Of Summer/Academic Year Learning Projects On The Academic Achievement Of Student Participants, Glenn Scott Beer

Doctoral Dissertations

This study examined differences in the academic achievement between students who participated in the Louisiana Gaining Early Awareness and Readiness for Undergraduate Programs (LA GEAR UP) Summer/Academic Year Learning Projects and students who did not participate in the program. The sample consisted of 111 students who attended schools participating in the LA GEAR UP program and who attended at least 4 LA GEAR UP summer learning camps and a comparison group of 111 students attending the same schools but who did not attend a summer learning camp. Participating students were individually matched with non-participants on 7 variables, including 6th-grade Iowa …

Computational Study Of Pristine And Titanium-Doped Sodium Alanates For Hydrogen Storage Applications, Gopi Krishna Phani Dathar

Doctoral Dissertations

The emphasis of this research is to study and elucidate the underlying mechanisms of reversible hydrogen storage in pristine and Ti-doped sodium aluminum hydrides using molecular modeling techniques. An early breakthrough in using complex metal hydrides as hydrogen storage materials is from the research on sodium alanates by Bogdanovic et al., in 1997 reporting reversible hydrogen storage is possible at moderate temperatures and pressures in transition metal doped sodium alanates. Anton reported titanium salts as the best catalysts compared to all other transition metal salts from his further research on transition metal doped sodium alanates. However, a few questions remained …

Chipless Rfid Sensor Tag System With Microstrip Transmissionline Based Id Generation Schemes, Sudhir Shrestha

Doctoral Dissertations

This dissertation presents a chipless radio frequency identification (RFID) sensor tag system consisting of passive chipless RFID sensor tags and specialized reader. The chipless sensor tags are fabricated on a flexible substrate and contain an ID generation circuit, a sensor, and a microstrip antenna. The ID generation circuit consists of meandered microstrip transmission lines and uses a novel reflection and delay based ID generation scheme. The scheme, using an input RF pulse, constructs an on-off keying (OOK) or pulse position modulated (PPM) signal pattern representing a unique ID code. Two transmission lines and OOK representation are used and the generation …

Naïve Bayes And Similarity Based Methods For Identifying Computer Users Using Keystroke Patterns, Shrijit S. Joshi

Doctoral Dissertations

In this dissertation, we present two methods for identifying computer users using keystroke patterns. In the first method "Competition between naïve Bayes models for user identification," a naïve Bayes model is created for each user. In the training phase of this method, the model of a user is trained using maximum likelihood estimation on the key press latency values extracted from the texts typed by the user. In the user identification phase of this method, for each user we determine the probabilistic likelihood that the typed text belongs to a user. Finally, the typed text is assigned to the user …

Infrared Light Activated Floating Micro Stimulators For Neuro-Prosthetic Applications, Kimberlyn M. Gray

Doctoral Dissertations

The most common failures in neural stimulation implants are due to interconnect complications such as tissue response, lead migration, and lead breakages. The challenge in eliminating interconnects lies in minimizing device size to maintain spatial selectivity required in the CNS. One approach to this problem is a current generating device that can be stimulated by an external signal, such as light or sound. Here, we report the design, construction and testing of rnicrophotodiode devices that can be stimulated remotely with near-infrared (NIR) light to generate current that can be injected locally into the peripheral nervous system. The use of near-infrared …

"Chasing A Ghost": Addressing The Opalescence/Aggregation Relationship Of An Igg 1 Antibody, John C. Champagne

Doctoral Dissertations

This study was conducted to address the aggregation/opalescence relationship of an IgG 1 therapeutic antibody under a variety of conditions. The opalescence characteristics of three antibodies, Mab 1, 2 and 3, were examined as a function of salt dependence, protein concentration and temperature, using a variety of biophysical techniques. The high molecular weight species were initially identified using batch static and dynamic light scattering and separated by asymmetric flow field flow fractionation. When the salt dependence was examined, any structural changes were characterized using differential scanning calorimetry, circular dichroism and fluorescence, while the association state and temperature dependence was measured …

A System Model For The Effect Of Polarization Mode Dispersion On Digital Modulated Optical Signals In Single Mode Fibers, Abhijit Shriram Chitambar

Doctoral Dissertations

A comprehensive systems model that retains the discrete nature of the output delay distribution in order to accurately characterize the pulse broadening due to Polarization Mode Dispersion (PMD) is developed in this thesis. PMD in optical channels has been a critical factor limiting high-speed data transmission over long distances in optical networks. PMD is a source of Inter Symbol Interference (ISI) and its impact increases with the transmission data rate. Since economical adaptive compensation schemes are currently unavailable, it is essential to characterize this impairment to completely understand its impact and develop effective countermeasures. An incremental approach has been developed …

Keeping Visual-Auditory Associations In Mind: The Impact Of Detail And Meaningfulness On Crossmodal Working Memory Load, Anne T. Gilman

Doctoral Dissertations

Complex objects have been found to take up more visual working memory---as measured by lowered change-detection accuracy with such stimuli---than simple colored shapes (Treisman, 2006; Xu, 2002). While verbal working memory studies have similarly shown reduced apparent capacity for longer words (Baddeley, 2007), other research has demonstrated that features contributing to object categorization and recognizability can help visual working memory capacity (Olsson & Poom, 2005; Alvarez & Cavanagh, 2004). Until very recently, no measures of crossmodal working memory capacity had been proposed, even though crossmodal associations are part of the fabric of learning, from classical conditioning to calculus. The working …

Sustainable Management Of Industrial Capital: Lca And Spatial Analysis In Decision Making For Beneficial Use Of Industrial By -Products, Alberta C. Carpenter

Doctoral Dissertations

The goal of this research was to broaden understanding of multiple impacts in assessing materials for construction. Life cycle assessment was used to this effect to understand the impacts from the use of industrial by-products for different applications on different spatial scales. The first two studies looked at applications in highway construction for a single project scenario and for a regional management scenario. The third study considered life cycle impacts for the management of construction and demolition (C&D) wood debris to include combustion for energy recovery. The fourth chapter reviews the literature for life cycle energy impact for building materials. …

Determination Of Geotechnical Properties Of Seafloor Sediment Using A Free Fall Penetrometer, Gopala Krishna Mulukutla

Doctoral Dissertations

A study was conducted to determine the penetration behavior of a cylindrical probe free falling to the seafloor and to utilize the data obtained to evaluate the engineering properties of surficial sediment. Two experimental probes, each equipped with accelerometers, pressure sensors and optical backscatter sensors were deployed in different sediment regimes. The data collected was used to derive the sediment type and determine physical properties such as undrained shear strength, coefficient of consolidation and shear modulus for soft fine-grained sediment.

Acceleration signals from drops of a free fall penetrometer contain information about the nature of the seafloor. A simple sediment …

The Maritime Revival: Antimodernity, Class, And Culture, 1870--1940, Glenn Michael Grasso

Doctoral Dissertations

Between 1870 and 1940, Americans redefined their perceptions, ideas, and cultural meanings of seafaring under sail. The Maritime Revival---a cultural phenomenon that took the workaday nineteenth-century maritime world and converted it into an archetypical exercise in essential Americanism---selectively picked stories, symbols, and specific lifestyles and elevated them to heroic status. Part of larger nineteenth-century revivalism, the Maritime Revival created an image of seafaring that was a small subset of the entire experience-as-lived. By the 1930s, Americans recognized a heroic, but lost, golden age of sailing ships that did not correspond to the maritime world that had once been a ubiquitous …

Temporal Variation, Regional Sources, And Removal Processes Of Volatile Organic Compounds In New England, Rachel S. Russo

Doctoral Dissertations

This dissertation describes three research projects with the common objective of characterizing the influence of volatile organic compounds (VOCs) on air quality in New England using measurements made over multiple years (2002-2008) and from different sampling locations. The specific objectives include identifying sources (direct emission or secondary production), quantifying mixing ratios, and characterizing the chemical (i.e., oxidation, photolysis) and physical (i.e., transport, mixing) processes which regulate the distributions of VOCs in the troposphere over southeastern New Hampshire.

Chapters 2 and 3 discuss the seasonal and interannual variability of nonmethane hydrocarbons (NMHCs), selected halocarbons, and alkyl nitrates using measurements from canister …

Synthesis And Characterization Of Functional Polymers With Controlled Architecture And Their Application As Anticorrosion Primers, Anne S. Quincy

Doctoral Dissertations

There are over 2900 ballast tanks in the U.S. Navy inventory and their annual maintenance cost amounted to 415 million dollars in 2006, half of which was directly correlated to corrosion. Ballast tanks which form the basic skeleton of a vessel, are subjected to very corrosive conditions. Epoxy based protective coatings are used by the Navy for minimizing corrosion and they currently offer five to seven years of protection. The work described in this thesis is in line with a major program instigated by the U.S. Navy to improve the reliability of tank coatings.

This thesis investigates the synthesis and …

Engaged Scholarship At Land-Grant Institutions: Factors Affecting Faculty Participation, Lisa Townson

Doctoral Dissertations

At a time when universities and their faculty are called to work in partnership with partners to address important societal issues, engaged scholarship has become an important movement in higher education. This research examines the perceptions of tenured and tenure-eligible faculty members at land-grant institutions and describes how disciplinary differences influence faculty members' expression of and likelihood to practice engaged scholarship; work with community partners; and how they perceive engaged scholarship is recognized and rewarded by their institutions. A stratified random sample of tenure-track faculty members from all 1862 land-grant institutions was surveyed via the Internet and data were analyzed …

Treatment Of Contaminated Sediments Using Reactive Cap Technology: Characterization And Modeling Of Geotechnical, Hydraulic And Contaminant Transport Behavior Of Cap-Sediment Systems, Rafael Antonio Prieto Piedrahita

Doctoral Dissertations

Reactive cap technology is a promising in-situ remediation solution for contaminated sediment, mainly because it has the potential to reduce costs and environmental impacts when compared to solutions that rely solely on dredging and disposal. Reactive capping mats have been recently used in demonstration projects as a passive remediation technology for contaminated sediment. The mats used in this research were comprised of two geosynthetic fabrics bound to a fibrous core filled with a reactive material. The type of geotextiles and reactive material are selected based on the characteristics of the contaminated material and the contaminants on site. The mat is …