Digital Commons Network^™

Recursive Non-Local Means Filter For Video Denoising, Redha A. Ali, Russell C. Hardie

Electrical and Computer Engineering Faculty Publications

In this paper, we propose a computationally efficient algorithm for video denoising that exploits temporal and spatial redundancy. The proposed method is based on non-local means (NLM). NLM methods have been applied successfully in various image denoising applications. In the single-frame NLM method, each output pixel is formed as a weighted sum of the center pixels of neighboring patches, within a given search window.

The weights are based on the patch intensity vector distances. The process requires computing vector distances for all of the patches in the search window. Direct extension of this method from 2D to 3D, for video …

Linear Elastic Mesh Deformation Via Localized Orthotropic Material Properties Optimized By The Adjoint Method, William L. Shoemake

Masters Theses and Doctoral Dissertations

The finite element method has been shown to be a powerful tool in computational engineering with recent application to electromagnetics and fluid dynamics. However, achieving the high orders of accuracy easily available to the finite element method has proven difficult due to conforming higher-order meshes to curved geometries. If higher-order nodes are not placed on the surface of the geometry error is introduced into the simulated solution. This barrier is largely a non-issue for inviscid meshes where a mid-edge node can be projected onto the nearest geometry surface with minimal detrimental side effects. Viscous meshes however have to deform most …

Identifying Users On Social Networking Using Pattern Recognition In Messages, Justin Joshuva

Masters Theses and Doctoral Dissertations

Online social networks, such as Facebook and Twitter, have become a huge part of many people's lives, often as their main means of communication with other people. Because of frequency of use and the apparent security measures of these sites, users often falsely believe the proffered identity of the person they are talking to. This blind belief sometimes results in security threats due to the passing of private or confidential information to the wrong user. This may lead to malicious readers getting a user's private information and using it illegally. This work proposes a mathematical model for identifying security threats …

The Regression Smoother Lowess: A Confidence Band That Allows Heteroscedasticity And Has Some Specified Simultaneous Probability Coverage, Rand Wilcox

Journal of Modern Applied Statistical Methods

Many nonparametric regression estimators (smoothers) have been proposed that provide a more flexible method for estimating the true regression line compared to using some of the more obvious parametric models. A basic goal when using any smoother is computing a confidence band for the true regression line. Let M(Y|X) be some conditional measure of location associated with the random variable Y, given X and let x be some specific value of the covariate. When using the LOWESS estimator, an extant method that assumes homoscedasticity can be used to compute a confidence interval for M(Y|X = x). A trivial way of …

Robust Measures Of Variable Importance For Multivariate Group Designs, Tolulope T. Sajobi, Lisa M. Lix

Journal of Modern Applied Statistical Methods

Variable importance measures based on discriminant analysis and multivariate analysis of variance are useful for identifying variables that discriminate between two groups in multivariate group designs. Variable importance measures are developed based on trimmed and Winsorized estimators for describing group differences in multivariate non-normal populations.

Effectively Comparing Differences In Proportions, Lonnie Turpin Jr.

Journal of Modern Applied Statistical Methods

A single framework of developing and implementing tests about proportions is outlined. It avoids some of the pitfalls of methods commonly put forward in an introductory data analysis course.

Missing Data In Longitudinal Surveys: A Comparison Of Performance Of Modern Techniques, Paola Zaninotto, Amanda Sacker

Journal of Modern Applied Statistical Methods

Using a simulation study, the performance of complete case analysis, full information maximum likelihood, multivariate normal imputation, multiple imputation by chained equations and two-fold fully conditional specification to handle missing data were compared in longitudinal surveys with continuous and binary outcomes, missing covariates, and an interaction term.

Around Gamma Lindley Distribution, Hamouda Messaadia, Halim Zeghdoudi

Journal of Modern Applied Statistical Methods

Some remarks and correction on a new distribution, Gamma Lindley, of which the Lindley distribution is a particular case, are given pertaining to its parameter space.

The Impact Of Inappropriate Modeling Of Cross-Classified Data Structures On Random-Slope Models, Feifei Ye, Laura Daniel

Journal of Modern Applied Statistical Methods

Previous studies that explored the impact of misspecification of cross-classified data structure as strictly hierarchical are limited to random intercept models. This study examined the effects of misspecification of a two-level, cross-classified, random effect model (CCREM) where both the level-1 intercept and slope were allowed to vary randomly. Results suggest that ignoring one of the crossed factors produced considerably underestimated standard errors for: 1) the regression coefficients of the level-1 predictor; 2) the inappropriately modeled predictor associated with the misspecified crossed factor; and 3) and their interaction. This misspecification also resulted in a significant inflation of the level-1 residual variances …

Facing The Sun, Frank Prendergast, Muiris O'Sullivan, Ken Williams, Gabriel Cooney

Articles

December 2017 marked 50 years since archaeologist Michael J. O’Kelly first observed the solar illumination of the burial chamber in the Neolithic passage tomb at Newgrange during the period of the winter solstice. O’Kelly subsequently recorded direct sunlight entering Newgrange through the ‘especially contrived slit which lies under the roof-box at the outer end of the passage roof’ on 21 December 1969. The discovery of this historic phenomenon, dating back over 5,000 years, captured the public interest and imagination at that time and ever since. In this major article published in the Winter 2017 edition of Archaeology Ireland (date of …

Design And Implementation Of A Stand-Alone Tool For Metabolic Simulations, Milad Ghiasi Rad

School of Computing: Dissertations, Theses, and Student Research

In this thesis, we present the design and implementation of a stand-alone tool for metabolic simulations. This system is able to integrate custom-built SBML models along with external user’s input information and produces the estimation of any reactants participating in the chain of the reactions in the provided model, e.g., ATP, Glucose, Insulin, for the given duration using numerical analysis and simulations. This tool offers the food intake arguments in the calculations to consider the personalized metabolic characteristics in the simulations. The tool has also been generalized to take into consideration of temporal genomic information and be flexible for simulation …

Multi-Sensor Fault Tolerant Learning Algorithm In An Agricultural Robotic System, Praditya Ajidarma

Open Access Theses

In recent years, more attempts on mechanization, intensification, and automation have been implemented to increase agricultural productivity. However, only few of the concepts are financially feasible for most agricultural fields, mostly due to the high cost of stationary on-ground sensors that is required in such concepts. In response to this issue, a novel approach of using sensor-mounted mobile robots to perform daily inspection has been proposed. By moving the sensors towards different object location, the investment cost is lowered and the framework become more affordable for most agricultural fields. In response to the background mentioned above, this research aims to …

Relative Importance Of Different Body Channels To The Believability Of A Stylized 3d Character Animation In A Full Body Shot, Saikiran Anasingaraju

Open Access Theses

Character animation involves movement in different channels of the character’s body. There is a norm in the animation industry that each of these different body channels has varying contributions to the believability of an acting performance: body movement being the highest contributor and lip sync the lowest. This thesis investigated this norm using statistical analysis. While the reduction of body motion caused the biggest drop in believability, similar reductions in facial animation and lip sync have not made a significant effect on the believability. The only exception to the above statement is the animation depicting the emotion sadness, where no …

Interactivity Factors In Visualization-Based Exploratory Search, Ali Baigelenov

Open Access Theses

Two of the main components of visualizations are representation and interaction. Several researchers have noted that the interaction component has been receiving less attention than the visual (representation) component. It was also noted by several researchers that there is currently no well-developed theoretical base for interaction research in information visualization. A number of important contributions to this problem were made, resulting in different frameworks that aimed to deal with various aspects of interaction design, such as benefits, costs, and techniques, to name a few. Despite the contributions and findings, the interactivity factors of diversity, complementarity, and fitness are still relatively …

What Are The Lived Challenges Experienced By Black Females In A Stem Doctoral Program At A Majority White Institution?, Sharlane S. Cleare

Open Access Theses

The purpose of this study is to explore the challenges experienced by Black female STEM doctoral students at a Majority White Institution. This study examined how, and to what extent did the Majority White Institution’s STEM environment infuenced such challenges. The qualitative phenomenological approach to this investigation utilized the lenses of Black Feminist Thought and Critical Race Feminism Theoretical Frameworks as interconnected lenses by which to conceptualize this phenomenon. This study answered the following question: What are the lived challenges experienced by Black female in a STEM doctoral program at a Majority White Institution? Purposeful and snowball sampling were employed …

Oxygen Diffusion Through Jp-8 As Related To Thermal-Oxidative Coking And Titania-Based Remediation Measures, John Wood Ellis

Open Access Theses

Thermal oxidative coking in jet engine injector passages leads to costly maintenance procedures as well as a significant decrease in engine efficiency. Research has shown that removing dissolved oxygen from the fuel before it reaches a heated passage can result in 1/70th of the coke buildup in injector passages [1]. However, the concern is that the high pressure, high temperature environment of an engine’s combustion chamber will cause the fuel to re-oxygenate rapidly, negating any positive effects of the de-oxygenating process. In connection with attempting to better understand and find solutions to the re-oxygenation leading to coking problem, the objective …

Using The Coulombian Approach To Model 3-D Forces, Torques, And Stable Positions In A Master / Slave Permanent Magnet System, James E. Davis Ii

Open Access Theses

Previous research in master and slave systems has demonstrated the effectiveness of using permanent magnets to perform remote functions. Different approaches have been utilized by authors to model the force interactions between two or more magnets. Limiting aspects such as solution time or models with limited geometry inspired the use of a different method.

The coulombian approach was used to model a master and slave system of neodymium magnets with complex 3-D orientation angles motivated by a previous prototype. The work demonstrated how the coulombian approach was applied to the master and slave system, how the force and torque interactions …

Nanosecond Electric Pulse Induced Changes Of Mammalian Cell Suspension Conductivity In Real Time, Andrew J. Fairbanks

Open Access Theses

Electric pulses (EPs) have been used for many biological applications from electrochemotherapy to wound healing. While conventional techniques use microsecond to millisecond pulses, more recent techniques use nanosecond EPs (NSEPs) with a much higher amplitude. Generally, the longer duration pulses fully charge the plasma membrane to permeabilize it in a process called electroporation. NSEPs fully charge the smaller intracellular organelles to enable the manipulation of intracellular function; however, they still partially charge the membrane to permeabilize it to facilitate the transport of smaller ions. Experiments have demonstrated this motion using dyes and long-term (on the order of minutes) electrical measurements. …

A Machine Learning Approach For Identifying The Effectiveness Of Simulation Tools For Conceptual Understanding, Sindhura Elluri

Open Access Theses

Interactive learning environments have been identified as promising technologies to improve teaching and learning in science and engineering. Specifically, simulation tools have become a vital part of coursework in both K-12 and higher education. It is therefore essential to identify better ways to integrate simulation tools in the classroom and at the same time provide teachers and students with feedback capabilities that can support existing assessment methods and provide opportunities for just-in-time teaching. One effective way to identify how students are benefiting from the use of computer simulations for conceptual learning is by having them explain the phenomena being explored. …

Performance Augmentation Of Compliance Based Morphing Wings Through Optimization And Non-Linearity, Ashwin Clement Henry

Open Access Theses

Conformal shape adaptation presents significant benefits in terms of increased aerodynamic efficiency for a wide range of flight conditions in addition to minimizing drag penalties via gap-less smooth shape profile change. Conformal shape adaptation in morphing wings can be achieved by distributed compliance and stiffness selectivity techniques. These morphing strategies yield light-weight monolithic structures by utilizing the multifunctionality offered by smart materials. The present thesis, therefore, attempts to enhance the performance of compliance based morphing wings by augmenting the stiffness characteristics through optimization of associated smart actuators and implementation of stiffness selectivity. These performance augmentation methods essentially attempt to improve …

Analytics Protocol For Data-Driven Decision-Making In The Construction Industry, Ashwini Jain

Open Access Theses

Due to the unique nature of construction projects and the need for leaders in the business to have knowledge from multiple fields, it has become difficult for decision makers to confidently make choices in their complex working environment. Over time, data availability and computational power have both improved. Moreover, technological advancements from the past few years have overwhelmed the industry by generating a diverse amount data from various sources. This large amount of data makes it possible to find nuggets of information. However, in this digital era, collecting data is not the problem, but how to extract useful information is …

Assessing The First And Last Mile Problem In Intercity Passenger Rail: Effects On Mode Choice And Trip Frequency, Lisa Lorena Losada Rojas

Open Access Theses

Passenger rail service is an integral part of intercity transportation networks, especially in areas where residents do not have access to cars or other intercity travel options. Some municipalities in the U.S. have experienced a decline in passenger rail service in recent years, which has prompted schedule reductions and entire abandonment of service in some cases. To improve the current intercity passenger rail service predicament, two alternatives can be considered: (1) improve the rail service itself (frequency, infrastructure, etc.) and (2) improve accessibility to the rail stations, which might be cheaper and more cost-effective overall. Improvements in accessibility can impact …

Mechanical Testing Of Semi-Solid Al-Mg Binary And 7050 Aluminum Alloys Using The Reheating-Cooling Method, Christopher James Mccleary

Open Access Theses

Elevated temperature tensile testing beyond the non-equilibrium solidus demonstrates the advantage of a new method called the Reheating-Cooling Method (RCM) for determining mechanical properties of Al-Mg binary alloys and cast alloy 7050 aluminum in the solid-liquid two phase mushy zone. Using the RCM, it is possible to achieve semi-solid tensile behavior with standard testing equipment and to retain a nonequilibrium casting microstructure, which is necessary to gain insight into hot tearing. Hot tearing, a virtually impossible to repair defect, is known to worsen with increasing Direct Chill (DC) cast ingot size. Further data gathered from mechanical testing of alloys within …

A Method For Assessing And Predicting Water Quality Status For Improved Decision- Making And Management, Valeria Mijares

Open Access Theses

With the increasing population and demand for water, it is crucial to be able to assess its quality on a real-time basis and for predictive purposes. Water-quality Indices (WQIs) provide a means by which the water quality can be compared across space and time based on a composite indicator. Index and subindex values can be used to flag contaminants of concern, guide prioritization of management efforts, and for predictive purposes. In this study, subindex formulations for key water quality parameters were developed and enhanced to incorporate water quality targets and criteria. The enhanced subindex formulations were built into the Unweighted …

Influence Maximization Using Observational Data, Mohith Murlidhar

Open Access Theses

Influence maximization is the problem of finding a subset of nodes (seed nodes) in a network, such that by incentivizing these set of nodes, one maximizes the expected spread of influence in the network. This is an NP hard problem for which in the past, greedy algorithms and heuristics have been proposed for solving the problem. Most of these algorithms on this topic have focused on using information about the underlying graph and the edge probabilities, while running expensive controlled experiment simulations to find a solution to the influence maximization problem. These algorithms also accounted only for direct (or indirect) …

Simplified Model For Persistent Sliding Contact, Adarsh Patil

Open Access Theses

Numerous engineering applications involve one or more mechanical components that come into contact with each other during operation. Repetitive motions under contact can lead to fatigue and wear problems in the components. When designing such components, it is important to characterize and quantify the stresses and strains in the contacting elements. This can be achieved by numerical simulation of the process and by using one of the several contact formulations available in most finite element software programs. However, contact is an inherently non-linear problem which is rather challenging even for the best commercial software programs currently available. Often contact simulations …

Orbit Maintenance Strategies For Sun-Earth/Moon Libration Point Missions: Parameter Selection For Target Point And Cauchy-Green Tensor Approaches, Vivek Muralidharan

Open Access Theses

The libration point orbits in the Sun-Earth/Moon system are formed by concurrent gravitational influences by various celestial bodies, originating in a nonlinear dynamical regime. Coupled with the unstable nature of the orbit, the impact of any perturbations are expected to increase rapidly. The feasibility of a flow-based, Cauchy-Green tensor control strategy for station-keeping is examined. An orbit consistent with the mission objectives is selected for examination. The station-keeping process is stochastic, thus Gaussian random errors are introduced for simulation. The evolution of a velocity perturbation over time is monitored, beyond which the attainable state in the accessible region nearest to …

Kalman Filtering For Lti Systems With State Dependent Packet Losses, Omanshu Thapliyal

Open Access Theses

Due to recent advances in networked control systems and wireless networked control systems, most systems of interest operate in environments susceptible to sensor malfunctions. The increased dependency on communication channels to transfer measurement data due to the geographical separation of sensors from actuators and plants further contributes to the issue. Most existing methods that deal with the problem of estimation under packet losses assume the packet arrival process to have stationary statistics. In this work we relax this assumption and address the problem of state estimation under state dependent packet losses. This problem presents inherent modeling of practical applications of …

Digimesh Reliability In High Speed Vehicular Applications, Bogdan A. Visan

Open Access Theses

In a fast-paced technological society, advances in wireless networking show potential to save lives. Communication is key to notifying Emergency Medical Services of a potentially deadly accident in near real-time. This paper will discuss the use of low powered wireless devices transmitting life-saving information autonomously. Current and planned technologies used in vehicles are built-in, costly, and vulnerable to physical destruction. Using an independent system can offer both old and new vehicles primary and secondary communication. The results from this research study show that vehicles can use DigiMesh as a viable solution, although relative velocity affects its performance.

Unsteady Aerodynamics And Blade-Row Interactions In The Embedded Stage Of An Axial Compressor, Douglas Ryan Matthews

Open Access Theses

In a mature engineering field like compressor aerodynamics, the most accessible advances in machine technology, translating to performance and efficiency, have been discovered and have found industry design applications. As the community continues to make progress, increasingly challenging aspects of the involved physics must be exploited. Modern turbomachinery operates with larger bypass ratios, smaller cores, and lighter, thinner, and more flexible materials resulting in the maintenance of higher operating pressures and temperatures. As the performance and efficiency of these machines continues to climb, the same technological advances reinforce challenges like forced-response vibration, high-cycle fatigue of engine components, and large relative …