Digital Commons Network^™

Modeling Of Equilibrium Point Trajectory Control In Human Arm Movements, Kai Chen

Dissertations

The underlying concept of the Equilibrium Point Hypothesis (EPH) is that the CNS provides a virtual trajectory of joint motion, representing spacing and timing, with actual movement dynamics being produced by interactions of limb inertia, muscle viscosity and speed/position feedback from muscle spindles. To counter criticisms of the EPH, investigators have proposed the use of complex virtual trajectories, non-linear damping, stiffness and time varying stiffness to the EPH model. While these features allow the EPH to adequately produce human joint velocities, they conflict with the EPH’s premise of simple pre-planned monotonic control of movement trajectory. As a result, this study …

Factors That Impact Seat Belt Usage And Injury Severity Of Belted Front Seat Occupants, Siri Konje Lawrencia Nukenine

Dissertations

Factors influencing seat belt usage have been extensively researched in the safety analysis literature. Most of this research has focused on factors that influence seat belt usage for a driver and front seat passenger in a vehicle. Few research studies have investigated factors that impact seat belt usage for back seat occupants. This research investigates the factors associated with seat belt usage for front-seat as well as backseat occupants of vehicles in the state of New Jersey. Using logistic regression, seat belt usage models were developed to examine the contribution of several variables on seat belt usage for five vehicle …

Study Of Mechanisms Of Phytotoxicity Of Alumina Nanoparticles, Anthony Elijius

Dissertations

Plant growth inhibitory effect of alumina nanoparticles has recently been reported (Ling Y, Watts D, 2004) but the mechanisms of such an effect are yet to be established. The phytotoxicity of aluminum and some of its compounds is well known, but the rapid expansion of nanotechnology resulting in the introduction of new sets of materials in the nanometer range has led to the development of new approaches, experimental methods and modes of investigation.

In this study, the observed phytotoxic effects of alumina nanoparticles suspension on five plant species (Zea mays, Cucumis sativus, Daucus carota, Brassica oleracea, Lactuca sativa) …

Mixing Of Nanosize Particles By Magnetically Assisted Impaction Techniques, James V. Scicolone

Dissertations

Nanoparticles and nanocomposites offer unique properties that arise from their small size, large surface area, and the interactions of phases at their interfaces, and are attractive for their potential to improve performance of drugs, biomaterials, catalysts and other highvalue- added materials. However, a major problem in utilizing nanoparticles is that they often lose their high surface area due to grain growth. Creating nanostructured composites where two or more nanosized constituents are intimately mixed can prevent this loss in surface area, but in order to obtain homogeneous mixing, de-agglomeration of the individual nanoparticle constituents is necessary.

Due to high surface area, …

A Molecular Dynamics Simulation Based Principal Component Analysis Framework For Computation Of Multi-Scale Modeling Of Protein And Its Interaction With Solvent, Tao Wu

Dissertations

This dissertation presents a new computational framework for calculating the normal modes and interactions of proteins, macromolecular assemblies and surrounding solvents. The framework employs a combination of molecular dynamics simulation (MD) and principal component analysis (PCA). It enables the capture and visualization of the molecules' normal modes and interactions over time scales that are computationally challenging. It also provides a starting point for experimental and further computational studies of protein conformational changes.

A protein's function is sometimes linked to its conformational flexibility. Normal mode analysis (NMA) and various extensions of it have provided insights into the conformational fluctuations associated with …

Modeling Of Magnetic Field Driven Simultaneous Assembly, Rene David Rivero

Dissertations

The Magnetic Field Driven Simultaneous Assembly (MFDSA) is a method that offers a non-statistical and deterministic solution to the problem of assembly via batch processing; a hybrid of serial and parallel processing. The technique requires the use of electromagnets as well as soft and hard magnetic materials that are applied to devices and recesses respectively. The MFDSA approach offers the ability to check and correct errors in real-time and is capable of scalable, versatile, and high-yield integration.

Devices, coated with a layer of soft magnetic material, are moved from initial to final positions along predetermined pathways through the action of …

Study Of Controlled Release Of Active Pharmaceutical Ingredients From Functionalized Nanoclays And Polymer Matrices, Jin Uk Ha

Dissertations

This dissertation contains the results of three related novel investigations in the field of structure-property-processing relationships of pharmaceutical polymer-based products. They are: a) modification of a pharmaceutical anionic nanoclay with two different Active Pharmaceutical Ingredients (APIs) to produce nanohybrid API carriers intended to be used alone or in acrylic polymer matrices, b) comparison of binary systems containing the above APIs in the selected acrylic polymers in terms of their miscibilities with the polymer, but in the absence of nanoclay, and c) comparison of the polymer/API binary systems with ternary polymer/API/Clay systems.

For the first study, the calcination method which can …

Face Recognition Using Multiple Features In Different Color Spaces, Zhiming Liu

Dissertations

Face recognition as a particular problem of pattern recognition has been attracting substantial attention from researchers in computer vision, pattern recognition, and machine learning. The recent Face Recognition Grand Challenge (FRGC) program reveals that uncontrolled illumination conditions pose grand challenges to face recognition performance. Most of the existing face recognition methods use gray-scale face images, which have been shown insufficient to tackle these challenges. To overcome this challenging problem in face recognition, this dissertation applies multiple features derived from the color images instead of the intensity images only.

First, this dissertation presents two face recognition methods, which operate in different …

Underwater Communication Via Particle Velocity Channels : Principles, Channel Models, And System Design, Huaihai Guo

Dissertations

A vector sensor is capable of measuring important non-scalar components of the acoustic field such as the particle velocity, which cannot be obtained by a single scalar pressure sensor. In the past few decades, extensive research has been conducted on the theory and design of vector sensors. On the other hand, underwater acoustic communication systems have been relying on scalar sensors only, which measure the pressure of the acoustic field. By taking advantage of the vector components of the acoustic field, such as the particle velocity, the vector sensor can be used for detecting the transmitted data. In this dissertation, …

Design Of Single-Carrier Frequency Domain Equalization (Sc-Fde) With Transmit Diversity For Wireless And Optical Communications, Kodzovi Acolatse

Dissertations

As the demand of wireless service is rising, there is a need to transmit high-speed packets over the wireless communication channel. Broadband data transmission over wireless channels commonly faces the challenges of multipath fading channels, which are both time and frequency selective. There is then a need to design transmission techniques that can combat the adverse effects of the channel, and enable reliable high data rate wireless services. Orthogonal frequency division multiplexing (OFDM) has become widely accepted primarily because of its robustness against frequency selective fading channels, but it suffers a number of drawbacks such as high peak-to-average power ratio …

Pattern Formation In Oscillatory Systems, Hui Wu

Dissertations

Synchronization is a kind of ordinary phenomenon in nature, the study of it includes many mathematical branches. Phase space is one of the most powerful inventions of modern mathematical science. There are two variables, the position and velocity, that can describe the 2-dimensional phase space system. For example, the state of pendulum may be specified by its position and its velocity, so its phase space is 2-dimensional. The state of the system at a given time has a unique corresponding point in the phase space. In order to describe the motion of an oscillator, we can talk about its motion …

Seismic Characterization Of Recycled Aggregate Concrete, Amin Jamali

Dissertations

There are significant environmental benefits of recycling waste concrete and reusing it as aggregate for structural concrete, but the use of Recycled Aggregate Concrete (RAC) is yet limited to non-structural applications such as road sub-base. Widespread application of RAC in areas such as seismic design requires an improved knowledge of RAC behavior under multiaxial state of stresses.

The main objective of this research is the characterization of seismic properties of RAC by developing a stress-strain model which can reasonably describe the behavior under both unconfined and confined conditions. An extensive experimental program, including testing of several plain RAC cylinders as …

Application Of Mass/Stiffness Eccentricity To Control Response Of Structures Subjected To Earthquake Ground Motion, Bakhtiar Feizi

Dissertations

This dissertation is driven by the concept that engaging more modes in the response of structures can be used to mitigate its translational dynamic response. One such an approach is to engage torsional modes through engineered eccentricity (mass/stiffness eccentricity), thus, introducing coupled translation-rotation response. This idea was first introduced in a paper published by MacBain and Spillers in 2004. As a follow up to the same idea this dissertation was an attempt to investigate and develop the theory concerning the application of mass/stiffness eccentricity to control the translational motion of structures subjected to earthquake ground motion.

Different discrete and continuous …

Tin/Hfo2/Sio2/Si Gate Stacks Reliability : Contribution Of Hfo2 And Interfacial Sio2 Layer, Nilufa Rahim

Dissertations

Hafnium Oxide based gate stacks are considered to be the potential candidates to replace SiO₂ in complementary metal-oxide-semiconductor (CMOS), as they reduce the gate leakage by over 100 times while keeping the device performance intact. Even though considerable performance improvement has been achieved, reliability of high-κ devices for the next generation of transistors (45nm and beyond) which has an interfacial layer (IL: typically SiO₂) between high-κ and the substrate, needs to be investigated. To understand the breakdown mechanism of high-κ/SiO₂ gate stack completely, it is important to study this multi-layer structure extensively. For example, (i) the …

Radio-Derived Three-Dimensional Structure Of A Solar Active Region, Samuel D. Tun

Dissertations

Solar active regions are the source of the most violent events observed on the Sun, some of which have a direct impact to modern civilization. Efforts to understand and predict such events require determination of the three-dimensional distributions of density, temperature, and magnetic fields above such active regions. This thesis presents the structure of the solar atmosphere above active region AR 10923, observed on 2006 Nov 10, as deduced from multi-wavelength studies including combined microwave observations from the Very Large Array (VLA) and the Owens Valley Solar Array (OVSA). The VLA observations provide excellent image quality at a few widely …

Distributed Synchronization Algorithms For Wireless Sensor Networks, Nicola Varanese

Dissertations

The ability to distribute time and frequency among a large population of interacting agents is of interest for diverse disciplines, inasmuch as it enables to carry out complex cooperative tasks. In a wireless sensor network (WSN), time/frequency synchronization allows the implementation of distributed signal processing and coding techniques, and the realization of coordinated access to the shared wireless medium. Large multi-hop WSN's constitute a new regime for network synchronization, as they call for the development of scalable, fully distributed synchronization algorithms. While most of previous research focused on synchronization at the application layer, this thesis considers synchronization at the lowest …

Model Reference Control For Ultra-High Precision Positioning Systems, Lan Yu

Dissertations

Due to the increasing demands of high-density semiconductors, molecular biology, optoelectronics, and MEMS/NEMS in the past decades, control of ultra-high precision positioning using piezoelectricity has become an important area because of its high displacement resolution, wide bandwidth, low power consumption, and potential low cost. However, the relatively small displacement range limits its application. This work proposed a practical ultra-high precision piezoelectric positioning system with a complementary high displacement range actuation technology. Solenoids are low cost, high speed electromagnetic actuators which are commonly used in on-off mode only because of the inherent high nonlinear force-stroke characteristics and unipolar forces (push/pull) generated …

A Retrospective Study Of Substance Use And Mental Health Disorders In A Sample Of Urban American Indian And Alaska Natives, Kathryn Aimee Fuller Phd

Dissertations

This retrospective study examined the prevalence of mental health disorders, co-occurring disorders (COD), and alcohol, tobacco, and other drug use (ATOD) among a sample of urban-dwelling adult American Indian and Alaska Natives (AI/ANs) seeking behavioral health services from one metropolitan Indian clinic in Southwestern United States. A descriptive quantitative design employed retrospective data from AI/AN subjects (N = 123) verified as tribally enrolled and receiving outpatient behavioral health services. Chart abstraction included patient demographics, substance use and mental health diagnoses, and ATOD scores from the Patient Health Questionnaire-9 (PHQ-9) and the Addiction Severity Index-NAV (ASI-NAV). The t-test compared gender differences …

Developing Anaerobic Digestion Cooperatives In Ireland, Aoife Ní Ruanaigh, John Mcgrory

Dissertations

Anaerobic Digestion (AD) is a natural process of decomposition and decay that takes place in the absence of oxygen and by which organic matter is broken down to its simpler chemical components. AD plants could help Ireland meet its requirements under a number of EU Directives as landfills release far more greenhouse gas emissions than other forms of waste treatment. It is estimated that 37 million tonnes per year of animal manure are stored on farms before disposal. There are also 676,000 tonnes of municipal food and garden waste produced annually. This waste could be used in AD plants to …

Vibration Based Technique For Monitoring The Postbuckling Deformation, Bashir Mustafa Ali

Dissertations

Structural health monitoring (SHM) is a technology whose objective is to detect damage growth in metallic and composite structural elements long before they reach critical dimensions. Most structural health monitoring approaches that have been developed in the past have confined their attention to material degradation such as cracks in metals and delaminations in composite materials. Buckling instability is another cause of catastrophic failure commonly seen in engineering structures. The objective of this study is to develop a technique capable of detecting the onset of buckling instability in structural members and assessing the margin of safety from final collapse. The technique …

Union Citezenship: Impact, Influences And Challenges To Irish Immigration Laws., Ewaen Fred Ogieriakhi

Dissertations

The objective of this thesis firstly, is to attempt to explore the impact, influences and challenges that European Union citizenship rules and the adoption of the Citizens Rights Directive has on the right of Union citizens and their family members to reside in Ireland. The thesis examines the shift from “Market Citizenship”- from having adequate financial resources and sickness health insurance for the acquisition of right of residence to now recognizing right of residence for economically inactive persons.¹ The thesis assesses the impact of the relevant Treaty provisions on Free movement of Persons and the case laws of the …

A Study Of Grade Level And Gender Differences In Divergent Thinking Among 8th And 11th Graders In A Mid-Western School District., Leah Christine Roue

Dissertations

No abstract provided.

Study Abroad Program Design, Personal Development And Intercultural Effectiveness, Margaret Davis Wiedenhoeft

Dissertations

Research on study abroad focuses on the development of learning outcomes and assessment (Bolen, 2007) or program design, such as level of integration with local student population, housing situation, and level of interaction with host culture (Brecht & Robinson, 1993; Engle & Engle, 2004; Georgetown Consortium Research Project, n.d.; Paige, Cohen, & Shively, 2004; Redden, 2007; Vande Berg, Balkcum, Scheid, & Whalen, 2004). The purpose of this study is to examine the extent of personal development and intercultural effectiveness of students who study abroad and to determine the relationship of program design (homestay, conducting an on-site project, language level obtained …

Teachers And Their Struggle With Personal Satisfaction As Young Mothers, Katherine Homer

Dissertations

The purpose of the study was to explore how the day-to-day experiences of teachers who are working mothers of young children shape their level of comfort and satisfaction with the dual role they live. This investigation also explored the dynamics of teacher retention by understanding the dilemmas female teachers with young families encounter. There is limited literature on working mothers who are high school teachers. There are many different issues this study examined to gain a better understanding of the complexities of the lives of women who are high school teachers while raising young children.

This study consisted of six …

The Role Of Experiential Learning In Nurturing Management Competenciesin Hospitality And Tourism Management Students: Perceptions From Students, Facultyand Industry Professionals, Kristen Jack

Dissertations

Previous research has revealed that industry professionals and educators in the field of Hospitality and Tourism Management (HTM) agree that classroom theory and experience in the field are essential components of undergraduate HTM education. Yet there is some disagreement on internship hour requirements, and limited data on actual outcomes. This study therefore examines the perceptions of students and industry professionals as to the extent HTM undergraduate students actually develop key management competencies while participating in experiential learning components. In addition, it captures the views of university faculty and hospitality industry professionals who work with these students regarding essential competencies and …

“Voluntary Sector-Rich” And “Voluntary Sector-Poor”: What Difference Does The Distinction Really Make?, Lindsey M. Mcdougle Phd

Dissertations

Nonprofit organizations serve a distinctive role within American society. Collectively, nonprofits are viewed as major sources of social capital, contributors to the public good, and the value guardians within communities. Nonprofits also have a sizeable (and quite positive) impact on the nation's economy. Despite the social and economic significance of nonprofits, though, research has shown that nonprofit organizations and resources are not always distributed evenly across communities. Indeed, Wolch (1990) has observed that some communities are voluntary sector-rich, while others are voluntary sector-poor. Therefore, many of the benefits often associated with the presence of nonprofits may not be actualized, or …

Spectroscopic Study Of New Sensors For Organophosphates, Metals, And Cyanide Based On Rhodamine And Cholic Acid Derivatives, Arambe Gedara Aruna Weerasinghe

Dissertations

Despite the increasing interest in developing sensors for nerve gas agents, efficient detection remains challenging. Among the various sensors developed so far, fluorescence sensors play an important role due to their simplicity. We developed six new rhodamine-based compounds that can be used as fluorescent turn-on sensors. Compound 1 and 3 gave high fluorescent enhancement with diethyl chlorophosphate (DCP) compared to the other compounds. Very high selectivity and sensitivity were observed as these compounds did not show significant fluorescent enhancement with dimethyl methylphosphonate (DMMP), HC1 and transition metal ions. The potential sensor can be used in solution as well as on …

Electron Transmission Characteristics And The Production Of Narrow Beams Using Glass Optics, Buddhika Senarath Dassanayake

Dissertations

Transmission of electrons through an insulating single cylindrically-shaped glass capillary of microscopic dimension has been investigated. Samples made with Borosilicate glass (PYREX 7740) were subjected to bombardment of 300-1000 eV electrons. Transmitted electrons were analyzed using a parallel-plate spectrometer coupled to a channel electron multiplier.

The transmitted electron intensity was found to decrease with increasing sample tilt angle relative to the direction of the primary beam. Two regions of transmission were found: direct where there is no interaction of the beam with the inner capillary wall, and indirect where the beam does interact with the wall. The rate of transmission …

Autonomy Through Social Skill Development: A Camp Intervention For Young People With Spina Bifida, Lauren Nicole Zurenda

Dissertations

Spina bifida is a complex condition that presents multiple physical and psychosocial challenges to autonomy development. Pediatric psychology may play a role in promoting autonomy development in this population through the implementation of empirically-supported, developmentally-appropriate, and syndrome-specific interventions. The current study was one attempt to meet the need for such interventions.

This study represents one step in a line of intervention research designed to promote autonomy gains among young people with spina bifida. Its purpose was to evaluate a manual-based curriculum as a part of a one-week long overnight camp exclusively for young people with spina bifida. It was hypothesized …

Mechanism For Pre-B Cell Loss In Mutant Ali/Ali Rabbits, Gregory Robert Robbins

Dissertations

Pre-B cell receptor (pre-BCR) signaling is a critical checkpoint in B cell development in which B-lineage cells expressing functional μ-chains undergo selective expansion. My dissertation work used a rabbit model system to study how VH structure affects the early stages of B cell development in the bone marrow (BM). Developing B cells in mutant ali/ali rabbits predominantly utilize VH4 during VDJ gene rearrangement. However, most of the VH4-utilizing B cells encounter a severe block early in B cell development. In contrast, wildtype rabbit B cells predominantly rearrange VH1, a gene >90% identical to VH4, and develop normally. We hypothesized that …