Digital Commons Network^™

A New Method For Failure Modes And Effects Analysis And Its Application In A Hydrokinetic Turbine System, Liang Xie

Masters Theses

"The traditional failure modes and effects analysis (FMEA) is a conceptual design methodology for dealing with potential failures. FMEA uses the risk priority number (RPN), which is the product of three ranked factors to prioritize risks of different failure modes. The three factors are occurrence, severity, and detection. However, the RPN may not be able to provide consistent evaluation of risks for the following reasons: the RPN has a high degree of subjectivity, it is difficult to compare different RPNs, and possible failures may be overlooked in the traditional FMEA method. The objective of this research is to develop a …

The Use Of Elemental Powder Mixes In Laser-Based Additive Manufacturing, Rodney Michael Clayton

Masters Theses

"This study examines the use and functionality of laser depositing alloys from mixes of elemental metallic powders. Through the use of laser-based additive manufacturing (LAM), near net-shaped 3-Dimensional metallic parts can be produced in a layer-by-layer fashion. It is customary for pre-alloyed powders to be used in this process. However, mixes of elemental powders can be used to produce alloys that are formed during the deposition process. This alternative technique requires that the elemental powders adequately mix during deposition for a homogeneous deposit to be produced. Cost savings and versatility are among several of the advantages to using elemental powder …

Protein Aggregation At Solid/Liquid Interfaces: A Monte Carlo Study With Explicit And Implicit Solvent Effects, Rehman Fazeem

Masters Theses

"Metropolis Monte Carlo (MC) simulations were performed with positively charged peptides in aqueous solution to study changes in peptide conformations at solid/liquid interface, and its effects on protein aggregation. Intermediate-resolution diblock model peptide, comprising of 10 units of ALA (non-polar) and LYS (polar) amino acid residues, was used for the simulations. In the first approach to modeling, solvent effects were considered explicitly. The explicit model was then used to study two peptide molecules, in helical structure, at solid/liquid interface. In order to increase the number of peptide molecules in the simulation box, with reduced computational cost, an implicit solvent model …

Libration Point Orbits Near Small Bodies In The Elliptic Restricted Three-Body Problem, Bharat Mahajan

Masters Theses

"In this study, the feasibility of using libration point orbits to explore small solar system bodies, including asteroids and comets, is considered. A novel design for a small body mission is proposed that makes use of libration point orbits as "parking" orbits. In considering a human exploration mission to asteroids or comets, these "parking" orbits may provide benefits including a safe vantage point for staging/observation, reduced perturbation effects from the nonuniform gravitational field of the body, fewer communication blackouts, ease of guidance and control of a lander on the surface, etc. Because small solar system bodies have extremely low mass …

Computational Fluid Dynamics Flow Comparison Between Openhole Sleeve And Plug-And-Perf Completion In A Hydraulic Fractured Horizontal Well, Viriyah Theppornprapakorn

Masters Theses

"Multi-stage hydraulic fracture completions in horizontal wells have facilitated economic development of natural gas from unconventional and tight gas reservoirs.Industry has relied on two horizontal multi-stage completion technologies: cemented and perforated liner or Plug-and-perf method and Openhole Sleeve Multi-stage method. Each method has its own advantages and disadvantages. However, one of the most important questions is which method yields better gas production? Computation fluid dynamics (CFD) is a powerful tool for solving complex fluid flow problems. In well completion design, CFD plays a significant role aiding the completion engineers on making decision on well completion methods. In this study, a …

Significance And Analysis Of Milia-Like Cysts In Dermoscopy Skin Lesion Images, Sneha K. Mahajan

Masters Theses

“Milia-like cysts (MLCs) are dermoscopic structures frequently observed in seborrheic keratoses(SKs), which are the most common type of skin lesions. Diverse appearances of these skin lesions make them difficult to differentiate from melanoma, a deadly type of skin cancer. Classified by size into two main groups, starry MLCs and cloudy MLCs, the presence of these structures in a skin lesion has been known to help differentiate benign lesions from melanoma. Though the presence of cloudy MLCs is not exclusively associated with SKs, they can be a useful tool to differentiate SKs from melanoma. This research study determines the statistical occurrence …

Sybil Detection In Vehicular Networks, Muhammad Ibrahim Almutaz

Masters Theses

"A Sybil attack is one where an adversary assumes multiple identities with the purpose of defeating an existing reputation system. When Sybil attacks are launched in vehicular networks, an added challenge in detecting malicious nodes is mobility that makes it increasingly difficult to tie a node to the location of attacks. In this thesis, we present an innovative protocol for Sybil detection in vehicular networks. Considering that vehicular networks are cyber-physical systems integrating cyber and physical components, our technique exploits well grounded results in the physical (i.e., transportation) domain to tackle the Sybil problem in the cyber domain. Compared to …

Improving Life Cycle Management Plans For Power Plant Components, Srinath Raghavan

Masters Theses

"Life cycle management (LCM) combines a set of technical and economic activities with the specific goal of improving the long term economic value of an asset. It is necessary to perform a sound LCM exercise on the utility or industrial asset to maintain the profitability of a plant. In most industries, the maintenance budget is either higher than optimal or lower than required, that result in expensive outages, damages and accidents. An LCM plan is a guide to make operational decision for a component over its life cycle. LCM typically consists of a preventive maintenance schedule, condition monitoring, inspection activities, …

Water Management Capabilities Of Bio-Inspired Flow Field Configurations For Polymer Electrolyte Membrane Fuel Cells, Nicholas Warren Freer

Masters Theses

"Fuel cells have received an increasing amount of attention over the past decade for their power production capabilities. Polymer electrolyte membrane (PEM) fuel cells in particular are researched because of their high power density, large range of operating conditions, green products, and ease of scalability. PEM fuel cells do have a number of issues that reduce their overall performance. These issues include variations in reactant distribution, materials issues for the bipolar plate, and flooding caused by poor water management. Variations in the reactant distribution causes lower overall power output due to regions of low reactant density. This means that optimizing …

Design And Analysis Of An Open-Ended Waveguide Probe For Material Characterization, Matthew Alan Kempin

Masters Theses

"Nondestructive evaluation of stratified (layered) composite structures at microwave and millimeter wave frequencies is of great interest in many applications where simultaneous determination of the complex dielectric properties and thicknesses of multiple layers is desired. Open-ended rectangular waveguide probes are effective tools for this purpose. The technique requires a full-wave electromagnetic model that accurately calculates the complex reflection coefficient as a function of frequency and material properties. Subsequently, this information is used in conjunction with the measured complex reflection coefficient to evaluate the sought for material properties. This thesis presents simulated and measured data to investigate the influence that measurement …

Social Cognitive Theory Vs. Social Comparison Theory: Examining The Relationship Between Social Influence And Weight Loss, Emily Grigg

Masters Theses

This qualitative study investigated the impact of social influence on weight loss, more specifically, the internal and external elements that effect response and success of those who are trying to lose weight. The research focused on three questions: (1) How great of an influence does self-efficacy have in weight loss success? (2) How great of an influence does social comparison have in weight loss success? (3) Which factor has the largest impact on weight loss: self-efficacy, peer efficacy, or positive social support, or negative social support? Data was collected by the researcher conducting semi-structured interviews. These interview were conducted with …

Service Learning And Social Justice: A Qualitative Study Of International Service Learning And Students' Perceptions Of Social Inequality, Sara Boro

Masters Theses

Using qualitative methodology the researcher analyzed the perspectives of students on service trips taken to Haiti by the Newman Catholic Center in (1) educating students about social injustice and (2) cultivating a desire for students to advocate for social change. Overall participants were impacted by their experience in Haiti. Participants articulated a deeper awareness and understanding of social inequality and of their own privilege. Participants also communicated a commitment to continue service, change their career plans and change their lifestyles. Student development occurred in three phases including pre-departure, experience, and re-entry. Engaged preparation, reflection, consequential connection, and human connection were …

A Decade Of Aid: The Increase, Impact And Alternative To Foreign Aid, Ryan Piers

Masters Theses

The first term of George H.W. Bush's presidency saw an increase in governmentally distributed foreign aid unparalleled in United States' history. This increase came at time in which the debate over the practicality of foreign aid had never been higher amongst academics. Historically, there are two separate branches of research in the study of foreign aid. The first examines the effects of the practice, while the other investigates the determinants of foreign aid, namely which donors give to which recipients and why. This study is twofold in a sense that it touches on both topics.

This thesis analyzed President George …

Improving The Rate Of Voluntary Compliance In Investigative Police Reporting Through The Application Of A Training Model And Job Aid, Kent D. Martin

Masters Theses

This study examines the immediate effect of a training module and job-aid on the percentage of police reports that lack pertinent information relating to the identity and contact information for suspects, witnesses and victims. A random sampling of reports was examined to determine if the initial responding officer obtained all available information needed to identify and contact these individuals for further investigation.

This analysis resulted in the creation of a training module, which was provided to all members of the patrol division. The module included a job aid to which each officer could refer during the report writing process. An …

Separating The Whites From The Chaff: Whiteness, Blackness, Racial Exclusion In The Midwest Agrarian Mind, Philip Mohr

Masters Theses

This thesis approaches the construction of race through the vantage of one agrarian magazine, the Prairie Farmer. It analyzes the rhetoric of the people who wrote for this magazine to distinguish changing attitudes toward whiteness and blackness in the rural and agricultural Midwest from the end of the Civil War to the Great Migration. While whiteness was equated with what the Prairie Farmer saw as the active, progressive farmer, blackness was associated with stupidity, laziness, and threat to property. From this, the thesis argues we can build a base of knowledge from which to analyze the roots of racism …

Demographics Of A Commercially Exploited Population Of Flathead Catfish (Pylodictis Olivaris) In The Wabash River, Cassi Jo Moody-Carpenter

Masters Theses

Flathead catfish, Pylodictis olivaris, are a popular game and commercial fish in the Midwestern United States. In the lower 322 km of the Wabash River, flathead catfish are commercially and recreationally harvested by Illinois and Indiana fishers. Current management regulations are different between the two states; Illinois and Indiana have minimum length limits of 381 and 254 mm, respectively. Indiana has proposed changing their minimum length limit to 381 mm and allowing only one fish> 889 mm to be harvested per day. My study examined the current status of flathead catfish in the Wabash River to determine a standardized …

The Caterpillar Game: A Classroom-Wide Behavior Intervention, Angela L. Boyle

Masters Theses

The Caterpillar Game, which was developed specifically for this study, is a classroom-wide behavior management system that uses reinforcement principles. The purpose of the study was to examine the effectiveness of the Caterpillar Game on first grade students' disruptive behavior. A concurrent multiple-baseline across settings was used to evaluate this intervention. Changes in disruptive behavior and teacher praise were evaluated through live classroom observations. Results suggest that the Caterpillar Game decreased student disruptive classroom behavior and increased teacher praise. Teacher satisfaction for the Caterpillar Game was also positive.

Direct - Drive Permanent Magnet Synchronous Generator Design For Hydrokinetic Energy Extraction, Amshumaan Raghunatha Kashyap

Masters Theses

"Hydrokinetic turbines deliver lower shaft speeds when compared to both steam and wind turbines. Hence, a water wheel generator must operate at speeds as low as 150 - 600 rpm. This thesis describes a permanent magnet synchronous generator (PMSG) that was designed, built, and tested to serve a low speed hydrokinetic turbine. The design methodology was emphasized since designing an application specific generator poses various design and hardware construction issues. These are torque, speed, power and start-up requirements. This generator was built to operate without a speed increaser, implying very low speeds. FEA and performance results from the simulation done …

Kinetics Of Human And Bovine Insulin Amyloid Fibril Formation In The Presence Of Solid/Liquid Interfaces, Paulina Barranco Morales

Masters Theses

"The purpose of this thesis was to study the rate and extent of aggregation of human and bovine insulin in bulk and in the presence of either polystyrene microspheres with different surface chemistries or liposomes of different composition. Insulin aggregation was followed by turbidimetry, Fourier transform infrared spectroscopy (FTIR), and dynamic light scattering. The Congo red assay was used to corroborate the presence of amyloid deposits and transmission electron microscopy (TEM) was used to analyze the morphology of the amyloid deposits. Our results show that not all the surfaces shortened the lag time. On the other hand, most surfaces had …

An Evaluation Of De-Embedding Techniques For Tsvs, Nicholas Garrett Erickson

Masters Theses

"One of the most important aspects of modern electronic designs is device measurement and characterization. Without device measurement and characterization, the functionality of end designs cannot be guaranteed. At the silicon level (on-wafer), extracting the electrical performance of devices and structures has grown increasingly more complex with the continual shrink of feature sizes. Compared to the overall measurement setup (VNA, cables, probes, interposers, etc.), the ultra small size of on-wafer structures leads to their electrical performance being easily overshadowed by other, larger fixtures. Thus, many scientists and engineers have worked to devise ever more accurate calibration and de-embedding techniques for …

Development Of An Optimization Model To Determine Sampling Levels, Zlatan Hamzic

Masters Theses

"As the complexity of multi-component products increases the quality of these products becomes increasingly difficult to control. The first step to manufacturing a quality product is making sure that the components of the product meet specifications. Product quality can be controlled through sampling inspection of the components. Two models were developed in this research to determine the optimal sampling levels for incoming lots containing parts for production and assembly of multi-component systems. The main objective of the first model is to minimize the expected cost that is associated with a nonconforming item reaching assembly. In this model the time available …

Wideband Characterization Of Printed Circuit Board Materials Up To 50 Ghz, Aleksei Rakov

Masters Theses

"A traveling-wave technique developed a few years ago in the Missouri S&T EMC Laboratory has been employed until now for characterization of PCB materials over a broad frequency range up to 30 GHz. This technique includes measuring S-parameters of the specially designed PCB test vehicles. An extension of the frequency range of printed circuit board laminate dielectric and copper foil characterization is an important problem. In this work, a new PCB test vehicle design for operating up to 50 GHz has been proposed. As the frequency range of measurements increases, the analysis of errors and uncertainties in measuring dielectric properties …

Fuzzy Logic Color Detection: Blue Areas In Dermoscopy Melanoma Images, Mounika Lingala

Masters Theses

"Malignant melanoma is one of the deadliest forms of skin cancer and is one of the most rapidly increasing cancers in the world. Image analysis techniques for the early detection of melanoma are dependent upon the detection of multiple color shades in melanoma images. Use of magnified visible-light imaging by dermoscopy allows detailed investigation of these color shades. This research explores the fuzzy logic methods for the detection and characterization of blue color shades to discriminate melanoma from benign skin lesions. Standard thresholds are placed on the RGB dermoscopy images firstly and then the restrictiveness is explored by implementing fuzzy …

Analysis Of Model Uncertainty In Hydraulic Modeling: The Bstem Application To The Osage River, Annabell Leigh Ulary

Masters Theses

"Uncertainty is inevitable when creating any kind of model. A model can be used in the most accurate way possible, if the uncertainties are understood. This study determines the level of uncertainty in the Bank Stability and Toe Erosion Model (BSTEM) of the Osage River downstream of Bagnell Dam between Lake Ozark, MO and Jefferson City, MO. The statistical analysis of the BSTEM model was performed using the aid of SAS statistical computer modeling software. There were 4 different analysis values used to determine the best fit model for all dependent variables. These values include the F-test, the coefficient of …

Parameter Optimization For Controlling Aluminum Loss When Laser Depositing Ti-6al-4v, Richard Charles Barclay

Masters Theses

"The ability to predict the mechanical properties of engineering materials is crucial to the manufacturing of advanced products. In the aerospace industry, Ti-6Al-4V is commonly used to build structures. Any deviation from the alloy's standard properties can prove detrimental. Thus, the compositional integrity of the material must be controlled. The ability to directly build and repair large, complicated structures directly from CAD files is highly sought after. Laser Metal Deposition (LMD) technology has the potential to deliver that ability. Before this process can gain widespread acceptance, however, a set of process parameters must be established that yield finished parts of …

Examining The Efficiency Of Multimodal Transportation Systems: A Systems Dynamics Approach, Lizzette Pérez-Lespier

Masters Theses

"With international trade becoming a big part of the world's economic activity, the demand for good freight transportation systems has grown substantially. The appropriate use of transportation is an integral part of the supply chain's effectiveness. Therefore, the continuous economic globalization, the growing demand for speed-to-market product delivery, and the need to manage global supply chains more effectively, has led to the sustained increase in demand towards multimodal transportation systems (MTS). MTS play an essential role in corporations competing in global markets in the 21st century. In transportation, the effectiveness and efficiency of the whole system depends upon the interconnectivity …

A Study Of Clustering Rssi And Lqi From Wireless Network Communications, Yanwen Wang

Masters Theses

"In today's information world, different wireless sensor network topologies are permitted to exist in the same geographical region. For example, a city contains thousands of enterprise networks; a school might include different wireless network topologies used by students and faculties respectively. Even within a building, there might be multiple companies that use their own wireless networks. These networks might cause interference to other networks. How to detect, determine and locate the unknown wireless topologies in the same geographical area becomes quite significant in the wireless industry, especially in military use, such as spy-nodes detection and communication orientation systems. In this …

Organizational Identity As A Promotional Tool: The Case Of The Panther Paw, Samantha L. Neal

Masters Theses

This paper examines a promotional campaign that was put together during the fall semester of 2012. The campaign was for a local bar, the Panther Paw Bar and Grill, and after data collection, it was determined that the main issue the bar suffered from was a lack of identity. So, with this knowledge, organizational identity was chosen as the main promotional tool for the campaign. The content of this paper outlines this process from start to finish including data collection, the plan put in place for the bar, and the promotional work that was done throughout the fall semester of …

The Effects Of A Communication Partner Training Program, Stephanie Fanale

Masters Theses

Historically, augmentative and alternative communication (AAC) intervention has focused on improving the communication skills of the individual using AAC, with limited support given to the communication partners of AAC users (Light, Dattilo, English, & Gutierrez, 1992). However, Carter & Maxwell (1998) contended that the skills of the communication partner are of equal importance as the AAC user's skills. In addition, many researchers have reported that family-centered intervention should be implemented in the AAC population (Bruno & Dribbon, 1998; Saito & Turnbull, 2007; Sigafoos et al., 2004). Unfortunately, few studies have directly measured communication partners' skills to measure progress or have …

Suicide Promotion Online: Frequency Of Access By High Risk Individuals, Daniel Stabin

Masters Theses

Online suicide promotion is a recent and potentially problematic phenomenon in which individuals provide detailed instructions for or encouragement to enact self-harm to other internet users. These types of resources are freely available to anyone willing to look for them, and there is no legal hindrance to prevent their continued operations. The purpose of this study was to investigate the frequency with which people in the general, nonclinical population access these sites with a particular interested in individuals experiencing depressive symptoms and in young adults. Both populations are likely to be influenced by suicide promotion. I predicted that individuals with …