Digital Commons Network^™

Effects Of Human Development On Aeolian Sediment Transport Rates Within An Adjacent Undeveloped Backshore Enclave, Kayla L. Kaplan

Theses

Sandy backshore enclaves are created where shorefront buildings are lost during high magnitude storms. Subsequent foredune growth in these enclaves is critical to providing protection to landward development. Conditions for foredune growth and sediment flux within an enclave can be influenced by the presence of adjacent buildings. The objectives of this research are to assess the following questions: what is the nature of sediment flux on a beach within an enclave, what are the potential constraints to transport on a beach within an enclave and, are natural processes alone able to sustain a foredune in an enclave. A field investigation …

Computational And Experimental Determination Of The Hydrodynamics In A Stirred Unbaffled Vessel Provided With Angle-Mounted Axial Impellers, Ji Ma

Theses

In most industrial applications, stirred tanks and reactors are typically provided with baffles to improve their mixing characteristics. However, in a number of pharmaceutical production facilities unbaffled vessels are commonly used. The absence of baffles is preferred in such cases because it reduces the potential for contamination and makes cleaning the vessel between batches easier. However, the lack of baffles also has a negative impact on the system’s hydrodynamics since it often results in poor mixing of the batch, especially if the impeller is centrally placed, since the liquid in such a system is subject to a strong tangential flow, …

A Study Of Kinematics And Kinetics In Time-Constrained Arm Movements, Oyindamola Owoeye

Theses

Several studies such as the equilibrium point hypothesis (EPH) purport that the motor signals that descend from the brain instead of encoding muscle torques, influence an existing relationship between muscle torque and body configuration.

In the present study, the possibility of torque depending explicitly on position was tested using a task in which subjects (N=5) moved a simulated weightless frictionless mass through a small (<8 degree) elbow extension in order to move a cursor on a screen to a target location. Each subject completed 720 trials. On ~10% of trials the simulated mass was increased unknown to the subject. The relationship between the cursor’s position and the torque applied to the system was held constant even when the simulated mass was increased. Thus, any change in torque produced was neither due the subjects’ perception of the mass nor due to their perception of the cursor. The time at which the subjects torque changed direction was seen to be significantly different (p<0.005) during trials which the mass changed. This change in torque is concluded to be position-dependent. However the possibility of this being a merely mechanical effect could not be ruled out by due to poor EMG collection.

A post-hoc analysis of different position-dependent motor control models, was done. Particularly, an exponential spring model, a linear spring model, and a linear spring with relative damping model were each tested to see how well …

Triplex Dna Receptor-Gold Nanoparticle Conjugates For Detection Of Oxidized Dna Base, Qingyu Xing

Theses

Oxidations of DNA nucleobases are believed to be one of the sources of aging and some age-dependent disease, such as cancer. Human body have various mechanisms to repair damaged DNA and base-excision-repair is one mechanism for removing those oxidized nucleobases. This mechanism processes in the cells by cutting the oxidized nucleobases from deoxyribose and letting them excrete though urine. Detection of those abnormal nucleobases in urine has been suggested as a convenient way of early cancer diagnosis. 5-OHU (5-hydroxyuracil), the oxidation product of cytosine, is one of those abnormal nucleobases and it potentially forms base pairs with all four DNA …

Realization Of Dynamixel Servo Plant Parameters To Improve Admittance Control For A Compliant Human-Robot Interaction, Ahmad Zahid Rao

Theses

In theory, admittance control offers a very effective method of implementing smooth human-robot interaction. It allows the user’s applied force to control the movement of a powerful robot as if the robot were a small, passive mass. However, the real-world application of admittance control faces limitation posed by the dynamics of servo motors, the accuracy of the force sensors, and the computation speed of processors.

This research investigates the limitations on achieving compliant passive behavior when using state-of-the-art actuators, sensors and processors. The work involves characterizing the dynamic behavior of the servo motors, development of improved differential equations representing admittance …

Comparison Of Muscle Synergies Elicited From Transcranial Meganetic Stimulation (Tms) And Voluntary Movements, Yifei Wei

Theses

A key question in motor control is the redundancy of musculoskeletal elements involved. This problem refers to as the degree of freedom problem. The Muscle Synergy Hypothesis is one of the hypotheses that aim to resolve the problem which defines that a muscle synergy is a combination of a small set of muscles activated at different levels, serving as a building block that constructs motor behaviors. A recent study (Overduin et al. 2012) demonstrated that muscle synergies decomposed by Nonnegative Matrix Factorization (NMF) from EMG patterns evoked by intra-cortical microsimulation (ICMS) in the monkey remarkably matched ones observed in naturalistic …

Semantics And Result Disambiguation For Keyword Search On Tree Data, Cem Aksoy

Dissertations

Keyword search is a popular technique for searching tree-structured data (e.g., XML, JSON) on the web because it frees the user from learning a complex query language and the structure of the data sources. However, the convenience of keyword search comes with drawbacks. The imprecision of the keyword queries usually results in a very large number of results of which only very few are relevant to the query. Multiple previous approaches have tried to address this problem. Some of them exploit structural and semantic properties of the tree data in order to filter out irrelevant results while others use a …

Plasticity Of The Cortical Representation Of Finger Extensors Induced By Paired Associative Stimulation, Ian Anthony Gerard Lafond

Dissertations

This dissertation first explored associative plasticity of the human motor cortical representation with the use of noninvasive transcranial magnetic stimulation (TMS) paired with peripheral electrical stimulation. Paired Associative Stimulation (PAS) has grown in popularity because of its potential clinical applications. PAS techniques are used in combination with electromyography (EMG) measurements to study cortical excitability and features of hand movement. This work focuses on a cohesive approach to answer central questions about: the ideal mechanism to facilitate cortical plasticity via PAS, the interaction between the behavior performed and type of stimulation delivered to the targeted cortical network and the effects of …

Generalized Dft: Extensions In Communications, Yuewen Wang

Dissertations

Discrete Fourier Transform (DFT) is a restricted version of Generalized DFT (GDFT) which offers a very limited number of sets to be used in a multicarrier communication system. In contrast, as an extension on Discrete Fourier Transform (DFT) from the linear phase to non-linear phase, the proposed GDFT provides many possible carrier sets of various lengths with comparable or better performance than DFT. The availability of the rich library of orthogonal constant amplitude transforms with good performance allows people to design adaptive systems where user code allocations are made dynamically to exploit the current channel conditions in order to deliver …

Task-Based User Profiling For Query Refinement (Toque), Chao Xu

Dissertations

The information needs of search engine users vary in complexity. Some simple needs can be satisfied by using a single query, while complicated ones require a series of queries spanning a period of time. A search task, consisting of a sequence of search queries serving the same information need, can be treated as an atomic unit for modeling user’s search preferences and has been applied in improving the accuracy of search results. However, existing studies on user search tasks mainly focus on applying user’s interests in re-ranking search results. Only few studies have examined the effects of utilizing search tasks …

Methods For The Direct Simulation Of Nanoscale Film Breakup And Contact Angles, Kyle Mahady

Dissertations

This thesis investigates direct simulation of fluids with free surfaces and contact lines, with a focus on capturing nanoscale physics in a continuum based computational framework. Free surfaces and contact lines have long presented some of the most challenging problems in computational fluid dynamics. Extensive progress has been made in recent years, and a wide variety of different methods are currently employed for direct simulation in these contexts. The complexity of the full governing equations for such flows poses significant challenges in terms of analytical techniques, and leads to lengthy computational times for direct simulations. For these reasons, reduced models …

Thermochemistry And Kinetics: Hydrogen Atom Addition Reactions With Alkenes, Oxidation Of Cyclopentadienone, Trifluoroethene And Transport Properties, Suriyakit Yommee

Dissertations

Thermochemical and transport properties and reaction kinetic parameters are important to understand and to model atmospheric chemistry, combustion and other thermal systems. These processes are all important to the environment. Thermochemical properties kinetic parameters and models for several atmospheric and combustion related chemical systems are determined using computational chemistry coupled with fundamentals of thermodynamics and statistical mechanics. Transport properties of hydrocarbon and oxygenated hydrocarbons which are important to the calculation of fluid dynamics of gas phase flow reactions and mixing needed for evaluation in the combustion and thermal (flow) fluid dynamic modeling. Transport properties of radicals cannot be measured so …

Social Analytics For Health Integration, Intelligence, And Monitoring, Xiang Ji

Dissertations

Nowadays, patient-generated social health data are abundant and Healthcare is changing from the authoritative provider-centric model to collaborative and patient-oriented care. The aim of this dissertation is to provide a Social Health Analytics framework to utilize social data to solve the interdisciplinary research challenges of Big Data Science and Health Informatics. Specific research issues and objectives are described below.

The first objective is semantic integration of heterogeneous health data sources, which can vary from structured to unstructured and include patient-generated social data as well as authoritative data. An information seeker has to spend time selecting information from many websites and …

Investigation Of Infinite-Dimensional Dynamical System Models Applicable To Granular Flows, Hao Wu

Dissertations

Recently Blackmore, Samulyak and Rosato developed a class of infinite-dimensional dynamical systems in the form of integro-partial differential equations, which have been called the BSR models. The BSR models were originally derived to model granular flows, but they actually have many additional applications in a variety of fields. BSR models have already been proven to be completely integrable infinite-dimensional Hamiltonian dynamical systems for perfectly elastic interactions in the case of one space dimension, but the well-posedness question of these systems is at least partially answered for the first time here. In particular, dynamical systems of the BSR type are proven …

Modeling The Controlled Delivery Power Grid, Vinit Madhukar Sahasrabudhe

Theses

Competitive energy markets, stricter regulation, and the integration of distributed renewable energy sources are forcing companies to reengineer energy production and distribution. The Controlled Delivery Power Grid is proposed as a novel approach to transport energy from generators to consumers. In this approach, energy distribution is performed in an asynchronous and distributed fashion. Much like the Internet, energy is delivered as addressable packets, which allow a controlled delivery of energy.

As a proof-of-concept of the controllable delivery grid, two experimental test beds, one with integrated energy storage and another with no energy storage, were designed and built to evaluate the …

Estudio De La Plástica Cinematográfica Digital, Edgar Meritano

STEM for Success Resources

La presente investigación versa sobre cómo la cinematografía con todas las intervenciones digitales que en ella se hacen ya no puede ser descrita meramente desde las teorías ópticas, toda vez que se les escapa el problema de la animación, la cual tiene las mismas capacidades de generación argumentativa espacio/temporal que la fotografía animada; y por el contrario, el registro óptico deviene en una técnica más en la paleta de posibilidades para llevar a cabo una película, convirtiéndose pues, en un recurso argumentativo, y no en la esencia de lo que es el cine.

Si bien en principio se trata de …

Continuous Monitoring Of Enterprise Risks: A Delphi Feasibility Study, Robert Baksa

Dissertations

A constantly evolving regulatory environment, increasing market pressure to improve operations, and rapidly changing business conditions are creating the need for ongoing assurance that organizational risks are continually and adequately mitigated. Enterprises are perpetually exposed to fraud, poor decision making and/or other inefficiencies that can lead to significant financial loss and/or increased levels of operating risk. Increasingly, Information Systems are being harnessed to reinvent the risk management process. One promising technology is Continuous Auditing, which seeks to transform the audit process from periodic reviews of a few transactions to a continuous review of all transactions. However, the highly integrated, rapidly …

Methods For Two-Sample Comparisons From Censored Time-To-Event Data, Nubyra Ahmed

Dissertations

In the analysis of censored survival data, it is frequently of interest to determine the efficacy of a treatment or new method over a control or existing method. For this purpose, one may report estimates of the two survival functions or, more specifically, their difference, accompanied by simultaneous confidence bands (SCBs). Alternatively, or in addition, one may conduct hypothesis testing for the difference of the two survival functions.

The first project exploits two bootstrap methods to develop new Wald-type SCBs for the difference of survival functions. The censored data bootstrap is employed to obtain nonparametric SCBs for the difference of …

Data Mining In Computational Proteomics And Genomics, Yang Song

Dissertations

This dissertation addresses data mining in bioinformatics by investigating two important problems, namely peak detection and structure matching. Peak detection is useful for biological pattern discovery while structure matching finds many applications in clustering and classification.

The first part of this dissertation focuses on elastic peak detection in 2D liquid chromatographic mass spectrometry (LC-MS) data used in proteomics research. These data can be modeled as a time series, in which the X-axis represents time points and the Y-axis represents intensity values. A peak occurs in a set of 2D LC-MS data when the sum of the intensity values in a …

Accounting For Midblock Pedestrian Activity In The Hcm 2010 Urban Street Segment Analysis, Albert Forde

Dissertations

The Urban Street segment analysis Chapter of the 2010 Highway Capacity Manual (HCM 2010) provides a methodology for analyzing automobile performance on signalized roadway segments within an urban roadway network. The methodology involves applying a platoon dispersion model to: a) predict the vehicle arrival flow profiles at a downstream signalized intersection; b) use the predicted arrivals to compute the proportion of vehicle arrivals on green; and c) subsequently estimate the delay, travel speed and Level of Service (LOS) under which the segment operates. Vehicles arriving during the red interval at a signalized intersection generally accumulate and form a platoon. When …

Multiple Testing Procedures For Complex Structured Hypotheses And Directional Decisions, Anjana Grandhi

Dissertations

Several multiple testing procedures are developed based on the inherent structure of the tested hypotheses and specific needs of data analysis. Incorporating the inherent structure of the hypotheses results in development of more powerful and situation-specific multiple testing procedures than existing ones. The focus of this dissertation is on developing multiple testing procedures that utilize the information on this structure of the hypotheses and aims at answering research questions while controlling appropriate error rates.

In the first part of the thesis, a mixed directional false discovery rate (mdFDR) controlling procedure is developed in the context of uterine fibroid gene expression …

Designing Novel Abstraction Networks For Ontology Summarization And Quality Assurance, Christopher Ochs

Dissertations

Biomedical ontologies are complex knowledge representation systems. Biomedical ontologies support interdisciplinary research, interoperability of medical systems, and Electronic Healthcare Record (EHR) encoding. Ontologies represent knowledge using concepts (entities) linked by relationships. Ontologies may contain hundreds of thousands of concepts and millions of relationships. For users, the size and complexity of ontologies make it difficult to comprehend “the big picture” of an ontology's content. For ontology editors, size and complexity make it difficult to uncover errors and inconsistencies. Errors in an ontology will ultimately affect applications that utilize the ontology.

In prior studies abstraction networks (AbNs) were developed to provide a …

Optimization Methods For Active And Passive Localization, Nil Garcia

Dissertations

Active and passive localization employing widely distributed sensors is a problem of interest in various fields. In active localization, such as in MIMO radar, transmitters emit signals that are reflected by the targets and collected by the receive sensors, whereas, in passive localization the sensors collect the signals emitted by the sources themselves. This dissertation studies optimization methods for high precision active and passive localization.

In the case of active localization, multiple transmit elements illuminate the targets from different directions. The signals emitted by the transmitters may differ in power and bandwidth. Such resources are often limited and distributed uniformly …

Information Filtering By Multiple Examples, Mingzhu Zhu

Dissertations

A key to successfully satisfy an information need lies in how users express it using keywords as queries. However, for many users, expressing their information needs using keywords is difficult, especially when the information need is complex. Search By Multiple Examples (SBME), a promising method for overcoming this problem, allows users to specify their information needs as a set of relevant documents rather than as a set of keywords.

Most of the studies on SBME adopt the Positive Unlabeled learning (PU learning) techniques by treating the user's provided examples (denoted as query examples) as positive set and the entire data …

Assessing Learning Outcomes And Social Capital Formation Resulting From The Use And Sharing Of Internet Knowledge Resources, Regina S. Collins

Dissertations

Today’s “digital natives” use the Internet to address most, if not all, their learning-related knowledge needs. This research evaluates the outcomes of formal learning activities requiring students to use, manage, share, and consolidate Internet knowledge resources (such as websites, videos, and blogs) to achieve both individual and group learning. This research takes an integrative approach to learning, capturing learner cognitive, interpersonal, and intrapersonal characteristics as well as the impact of the digital environment by evaluating the technological affordances of two different systems supporting such learning activities. This research also examines pedagogical modifications that would best integrate course assignments utilizing Internet …

Development Of Flexible Batteries Using Nano-Carbons And Polymers, Zhiqian Wang

Dissertations

Flexible electronics such as wearable equipment, displays, cell phones and smart cards require flexible power sources like batteries. In this thesis, the development of flexible batteries and supercapacitors are presented. Different types of flexible batteries including zinc carbon batteries, primary alkaline batteries, secondary alkaline batteries and zinc air cells are presented, These were designed, fabricated and improved using polymers and nano-carbons like carbon nanotubes (CNTs). CNTs are found to be effective as conductive additives compared to the traditional graphite. Purification is important to remove impurities that lead to side reactions/ corrosions. However, further treatment like carboxylation lead to higher electric …

An Efficient Boundary Integral Method For Stiff Fluid Interface Problems, Oleksiy Varfolomiyev

Dissertations

The purpose of this thesis is to formulate and investigate a boundary integral method for the solution of the internal waves/Rayleigh-Taylor problem. This problem describes the evolution of the interface between two immiscible, inviscid, incompressible, irrotational fluids of different density in three dimensions. A mathematical model of this interfacial flow problem in 3D is derived. The motion of the interface and fluids is driven by the action of a gravity force, surface tension at the interface, elastic bending and/or a prescribed far-field pressure gradient. The presented models include derived equations for the evolution of the interface and dipole density on …

Principles And Applications Of Mechanical Dry Coating - Review And State-Of-The-Art, Sayani Bhaumik

Theses

Dry Coating of powders to form composite particulates has been firmly established and has garnered interest both in academia and industry due to its myriad applications. This thesis work is an attempt to map the progress of the dry coating technology from its incipient years in the '80s to the thriving practice in the present day. Dry coating is a relatively simple approach to coat powders with specific guest particles via mechanical means to produce composites with desired tailor-made properties, without the constraints of harmful emissions or huge capital investment. Composite particulates with enhanced flowability, high-temperature resistant properties, and modified …

Characterizing Alma For Solar Observation, Yi Chai

Theses

ALMA (Atacama Large Millimeter/submillimeter Array) is an antenna array of 66 antennas located in northern Chile at 5000 meters altitude. It is the largest ground-based array operated at millimeter/submillimeter wavelengths. In this thesis, the advantages of using ALMA for solar observation are presented, together with the introduction of a campaign to commission ALMA for solar observations. Observation modes of the solar campaign are reviewed in Chapter 2. Methods for constructing images from single dish data as well as the procedure for processing interferometer data, including calibration and imaging, are given in Chapter 3. The CLEAN algorithm that is used for …

Modeling Of Electrical Behavior Of Graphene-Based Ultracapacitors, Patrick Dzisah

Theses

Graphene has been identified as a promising material for energy storage, especially for high performance ultracapacitors. Graphene-based ultracapacitors show high stability, significantly-improved capacitance and energy density with fast charging and discharging time at a high current density, due to enhanced ionic electrolyte accessibility in deeper regions. The surface area of a single graphene sheet is 2630 m2/g, substantially higher than values derived from Brunauer Emmett Teller (BET) surface area measurements of activated carbons used in the current electrochemical double layer capacitors.

In an ultracapacitor cell, chemically modified graphene (CMG) materials demonstrate high specific capacitances of 135 and 99 F/g in …