Digital Commons Network^™

Parameter Determination And Experimental Validation Of A Wire Feed Additive Manufacturing Model, Kannan Suresh Kumar

Masters Theses

“Laser metal deposition is an additive manufacturing method with great scope and robustness. The wire fed additive manufacturing method has great opportunities in space applications and other zero gravity manufacturing processes. Process parameters play an important role in controlling the complex phenomenon and obtaining an ideal manufactured part. These parameters can be efficiently determined using simulation tools which are highly essential in visualizing real world experiments, therefore saving time and experimental costs. The objective of this study is to develop a transient 3D model of laser aided wire feed metal deposition which realizes the heat transfer and fluid flow behavior …

Adaptable Ring, Bayes Theorem And Dual Gradient Analysis: An Approach To Automatic Shape Detection, Skin Lesion Segmentation And Focus Detection Respectively For Medical Image Analysis, Kanakam T. Maddala

Masters Theses

“Vision-based applications are increasing with the increase in technology and are making a huge impact in this global civilization. A vision-based measurement approach for pill shape detection was developed for medical pill identification, a focus detection method was developed for digital dermoscopy, and a machine learning approach was used for automatic lesion segmentation, which assists in automatic melanoma diagnosis. Rapid and accurate pill identification is needed by medical and law enforcement personnel during emergencies. But, one of the main parameters in pill identification is the shape of the pill. An Adaptable-Ring approach describes a novel technique to accurately detect the …

Online Diagnosis Of Diabetes With Twitter Data, Farheen Ali

Masters Theses

"Innovation in technology enables people to communicate, share information and look for their needs by just sitting in rooms and going through some clicks. While social media has played a very important role in connecting people worldwide, its potential has stretched beyond the innovative idea of connecting people through their social networks. While many thought there was no meeting point for the healthcare sector and social media, it was a surprise when research and innovations have shown that social media could lay a very significant role in the health care sector.

Research has been done in developing models that could …

Evaluation Of Millimeter-Sized Preformed Particle Gel For Conformance Control Treatments Using Simple Models, Ali Abdulmohsen Al Brahim

Masters Theses

Millimeter-sized preformed particle gels (PPGs) have been successfully used to tackle the high-permeable zones, fractures and channels in mature oilfields for conformance control improvement. PPGs can significantly reduce the permeability of abnormal fractures and divert injected water to the low permeable zones where hydrocarbon was not swept by previous water flooding. Due to the irregularity of PPGs in shapes after swollen, their strength cannot be easily measured using the conventional methods. Therefore, the open hole screen plate models with various hole diameters and density were designed to establish a simple technique that can be used to measure the strength of …

Determining Rockfall Volumes In Three Sites Along Habs Mountain Road In Southwestern Saudi Arabia, Using Lidar Technology, Abdullah Ayed Al-Otaibi

Masters Theses

"The rugged elevated topography is a characteristic feature of the western and southwestern regions of Saudi Arabia. Few arterial roads connect the scattered villages of these regions to major cities, such as Habs Road in Jazan region. Rock fall poses a serious hazard to people, property and animals along the rock cuts of this road. Although no traditional Rockfall studies have previously been applied to this road, accessibility and rock formation shape and structure variability influenced the choice of using Terrestrial Light Detection And Ranging (LiDAR) technology to calculate the volume of rockfall at selected sites along this road.

Software …

Palynological Interpretations Of Deep Sea Drilling Projects Cores In The Gulf Of Mexico And Bahamian Platform, Adam Patrick Barron

Masters Theses

"One hundred drill core samples were from Deep Sea Drilling Project (DSDP) Sites 94, 98, and 540 were investigated for their palynological contents (pollen, spores, acritarchs, dinoflagellate cysts, and dispersed organic matter) to infer the paleoenvironmental and paleoceanographic history of the Gulf of Mexico and the Bahamian Platform during the middle Eocene to middle Miocene interval. At Sites 94 and 540, abundant dinoflagellate cysts (chiefly Operculodinium centrocarpum, Lingulodinium machaerophorum, Impagidinium sp., Nematosphaeropsis sp., and Spiniferites spp.) were used as paleoenvironmental indicators. Two alternating palynofacies assemblages were identified from dispersed organic matter analysis: terrestrially influenced assemblage A and marine dominated assemblage …

Impact Of Configuration Variations On Small Modular Reactor Core Performance, William Kirby Compton

Masters Theses

"One of the most promising new reactor designs is the Small Modular Reactor (SMR). These reactors, which operate under 300 MWe, will help bring cheap and safe nuclear energy to remote and centralized locations alike. Their ease of construction, advanced passive safety features, and cost effectiveness make these reactors an intriguing option for the near future.

In the work presented here, a neutronics analysis of the Westinghouse SMR was performed. Westinghouse's SMR design is a scaled down version of their AP1000 plant and will produce about 225 MWe of power. Though the parameters of the reactor core will be modeled …

American Sign Language Alphabet Recognition Using Microsoft Kinect, Cao Dong

Masters Theses

"American Sign Language (ASL) fingerspelling recognition using marker-less vision sensors is a challenging task due to the complexity of ASL signs, self-occlusion of the hand, and limited resolution of the sensors. This thesis describes a new method for ASL fingerspelling recognition using a low-cost vision camera, which is Microsoft's Kinect. A segmented hand configuration is first obtained by using a depth contrast feature based per-pixel classification algorithm. Then, a hierarchical mode-finding method is developed and implemented to localize hand joint positions under kinematic constraints. Finally, a Random Decision Forest (RDF) classifier is built to recognize ASL signs according to the …

Evaluation Of Preformed Particle Gel Treatment Using Homogeneous And Heterogeneous Models, Hilary Ogochukwu Elue

Masters Theses

"This research investigates the effects of preformed particle gel (PPG) in remedying the problems of excess water production and low oil recovery of heterogeneous reservoirs by placing the PPG in the high-permeability layer, thus diverting displacing brine to the unswept low permeability layer. This investigation was completed with three tasks.

The first task was to evaluate the PPG swelling kinetics and strength as a function of concentration of brine. The result of this task indicate that PPG prepared with low concentration of brine swells more, becomes weaker, more deformable than PPG prepared with high concentration of brine.

The second task …

Pipeline Leak Detection, Marcia Golmohamadi

Masters Theses

"In the present research two techniques are applied for leak detection in pipelines. The first method is a hardware-based technique which uses ultrasonic wave's emission for pipeline inspection. Ultrasonic waves are propagated in the pipe walls and reflected signal from leakage will be used for pipe analysis. Several Pipes with various dimensions and characteristics are modeled by finite element method using ANSYS. Second order longitudinal modes of ultrasonic waves are emitted in their walls. For this purpose, excited frequency is calculated such that it excites the second order longitude mode. In order to investigate the behavior of emitted wave in …

Emission And Energy Analysis Of Self-Sufficient Biomass Power Plant To Achieve Near Net Zero Co₂ Emission, Baburaj Kanagarajan

Masters Theses

"The use of biomass to fuel power plants is considered by many to be a carbon neutral solution to carbon dioxide emissions. One objection to this method of power generation is the gasoline or diesel spent in the transportation and feedstock production, which is a major contributor to carbon emission. In addition, costs associated with the transportation of the biomass fuels are also a major limiting. This work investigates the use of a hybrid farming facility as a means of distributed generation combined. A model that incorporates a small scale biomass power facility located within a farming facility is examined. …

Thermographic Investigation Of Laser Metal Deposition, Sreekar Karnati

Masters Theses

"Laser metal deposition as an additive manufacturing technique has been proven to possess the capability for fabricating complex, intricate geometries and excellent material properties through material deposition. Accurate manufacture of such geometric features would require precise control over the material deposition process. The need of the hour are process monitoring and analyses mechanisms that are crucial in ascertaining the occurrence of the intended actions during deposition while also serving as effective learning tools. The current work involved developing and incorporating an Infra-Red (IR) camera as a process monitoring tool for laser metal deposition. Using the IR camera the thermal dynamics …

Application Of Loglinear Models To Claims Triangle Runoff Data, Netanya Lee Martin

Masters Theses

"In this thesis, we presented in detail different aspects of Verrall's chain ladder method and their advantages and disadvantages. Insurance companies must ensure there are enough reserves to cover future claims. To that end, it is useful to estimate mean expected losses. The chain ladder technique under a general linear model is the most widely used method for such estimation in property and casualty insurance. Verrall's chain ladder technique develops estimators for loss development ratios, mean expected ultimate claims, Bayesian premiums, and Bühlmann credibility premiums. The chain ladder technique can be used to estimate loss development in cases where data …

Design And Implementation Of A 20 Ghz Ultra-Wide Bandwidth Channel Emulator For Differential High Speed Serial Data Links, Wei Qian

Masters Theses

"High speed serial link is now the dominant signal propagation design in various communication, computing and embedded applications. Emulation of such channels is important in signal integrity design and product testing, where full channel simulation is restricted due to the need for protection of intellectual property and frequent channel reconfiguration. This thesis introduces robust lossy material and FIR filter design methods that can be used for channel emulation to provide a solution under these restrictions. Based on the channel characterizations normally obtained in the frequency domain by vector network analysis, different emulation strategies and optimization techniques are utilized to emulate …

Signal Integrity Analysis Of A Low Cost Pcb To Pcb System, Kancy Robison

Masters Theses

"This report presents the analysis of a low cost PCB to PCB cable and connector system focusing on its data rate limitations and optimizing transmitter and receiver operations. Economic factors have an ineluctable presence in digital hardware engineering and, as data rates are continually pushed to new bounds, finding cheaper alternatives in hardware while maintaining performance standards becomes more relevant. This study will show the measurement and simulation of a low cost digital system which includes a PCB board, connector, and a multi-pin flex cable (ribbon cable). These S-parameter and TDR measurements/simulations are used to gain an intuition for the …

A New Technique For Modeling The Geomorphology Of A Slow Moving, Soft-Slope Landslide Using Terrestrial Lidar, Nathan Bradley Rohrbaugh

Masters Theses

"Soft slope movement is a big problem whether it involves an engineered slope, one that is near infrastructure, or both. Active landslides that fail slowly sometimes allow ample time to affect remedial works. In order to plan effective remedial works, there needs to be a model of the entire geometry of the slide. This thesis describes a new approach to evaluate the morphology of slope geometry using Light Detection and Ranging (LiDAR) data obtained from simple targets strategically positioned on a slide body. The data was gathered in three-month intervals over a period of one year to allow enough time …

Energy Disaggregation In Nialm Using Hidden Markov Models, Anusha Sankara

Masters Theses

"This work presents an appliance disaggregation technique to handle the fundamental goal of the Non-Intrusive Appliance Load Monitoring (NIALM) problem i.e., a simple breakdown of an appliance level energy consumption of a house. It also presents the modeling of individual appliances as load models using hidden Markov models and combined appliances as a single load model using factorial hidden Markov models. Granularity of the power readings of the disaggregated appliances matches with that of the readings collected at the service entrance. Accuracy of the proposed algorithm is evaluated using publicly released Tracebase data sets and UK-DALE data sets at various …

Experimental And Computational Evaluation Of Water Management And Performance Of A Bio-Inspired Pem Fuel Cell In Comparison To A Conventional Flow Field, Venkatanaga Bhaskar Prakash Saripella

Masters Theses

"Fuel cells are being increasingly used in various stationary and transportation power applications due to their higher energy efficiency and lower pollution. Flow field design in Proton Exchange Membrane (PEM) fuel cells is a major area of research for performance improvement. Bio-inspired flow field designs have significant potential for increased performance by effective distribution of reactants with better water management capabilities. In this study, a bio-inspired flow field design, formulated using Murray's law and mimicking a typical leaf venation pattern, is experimentally and computationally investigated in comparison to a conventional single serpentine design. Experiments are conducted using a special transparent …

Fuzzy Adaptive Resonance Theory: Applications And Extensions, Clayton Parker Smith

Masters Theses

"Adaptive Resonance Theory, ART, is a powerful clustering tool for learning arbitrary patterns in a self-organizing manner. In this research, two papers are presented that examine the extensibility and applications of ART. The first paper examines a means to boost ART performance by assigning each cluster a vigilance value, instead of a single value for the whole ART module. A Particle Swarm Optimization technique is used to search for desirable vigilance values. In the second paper, it is shown how ART, and clustering in general, can be a useful tool in preprocessing time series data. Clustering quantization attempts to meaningfully …

The Effects Of Physical Flash Hole Deviations On Factory-Grade Rifle Ammunition, Nicolaas Martin Schrier

Masters Theses

"The objective of this research is to determine the effect of dimensional and positional changes of the primer flash hole on the performance of factory-grade rifle ammunition. The studied variables were flash hole diameter, offset from center, and orientation of the offset in the primer pocket. Cartridge performance was quantified by measuring muzzle velocity, chamber pressure, and target grouping size (precision).

Five different flash hole diameters were tested for both the Remington .223 and Winchester .308 calibers: 1.4mm, 2.0mm (the Fiocchi standard), 2.4mm, 2.8mm, and 3.0mm. Each diameter was tested at three offsets: centered (no offset), 0.5mm from center, and …

Behavior Of Crimped Cold-Formed Steel C-Section Beams, Jeffrey Devon Smith

Masters Theses

"This work covers the behavior of crimped cold-formed steel C-section beams under flexural loading. The specific beam shape that was tested was 600S162-54. The crimps were placed in the flange and web of the beam to curve the beam. Three crimp sizes were tested: 0.5 degree, 1.5 degree, and 3.0 degree. In construction practice, the company placed a reinforcing steel band that overlapped the crimped areas to restore strength. These various crimp degrees were tested to evaluate how much strength, if any, was lost. The reinforcing steel band was tested simultaneously with the beam to evaluate if its presence significantly …

Compressed Sensing Techniques For Radial Ultra-Short Echo Time (Ute) Magnetic Resonance Imaging, Xiahan Yang

Masters Theses

"This thesis proposes two techniques, namely Compressed Sensing (CS) and self-gating, for pre-clinical (CMRI) to reduce scan time and RF exposure to mouse heart, simply experimental procedures, and improve imaging quality. The proposed CS technique reduces the number of radial trajectories in Ultra-short Echo Time (UTE) CMRI scans on a 7 Tesla MRI machine to acquire 13% to 38% of the fully sampled k-space data. To reconstruct the image, the Non-Uniform Fast Fourier Transform (NUFFT) is utilized in each iteration of the l1-norm optimization algorithm of the CS to reduce error and aliasing. Experimental results with a phantom and a …

Co₂ Miscible Flooding Application And Screening Criteria, Mingfei Yin

Masters Theses

"Field experience has shown that CO₂ miscible flooding is an effective method to improve oil recovery, but only with proper reservoir candidate selection and optimal project design. This paper discusses both CO₂ miscible and immiscible flooding mechanisms and offers some guidelines for flooding operations. New developments in MMP determination are also introduced.

This research is based on a summary of field data from 134 CO₂ projects in the U.S. Several numerical methods have been applied for data cleaning. After cleaning, data from 128 projects have been analyzed and correlated. Carbonate reservoirs and sandstone reservoirs are the two …

Rote-Lcs Learning Classifier System For Classification And Prediction, Benjamin Daniels

Masters Theses

"Machine Learning (ML) involves the use of computer algorithms to solve for approximate solutions to problems with large, complex search spaces. Such problems have no known solution method, and search spaces too large to allow brute force search to be feasible. Evolutionary algorithms (EA) are a subset of machine learning algorithms which simulate fundamental concepts of evolution. EAs do not guarantee a perfect solution, but rather facilitate convergence to a solution of which the accuracy depends on a given EA's learning architecture and the dynamics of the problem.

Learning classifier systems (LCS) are algorithms comprising a subset of EAs. The …

A Novel Entropy Production Based Full-Chip Tsv Fatigue Analysis, Tianchen Wang

Masters Theses

"Through-silicon vias (TSVs) are subject to thermal fatigue due to stress over time, no matter how small the stress is. Existing works on TSV fatigue all rely on measurement-based parameters to estimate the lifetime, and cannot consider detailed thermal profiles. In this paper, we propose a new method for TSV fatigue prediction using entropy production during thermal cycles. By combining thermodynamics and mechanics laws, the fatigue process can be quantitatively evaluated with detailed thermal profiles. Experimental results show that interestingly, the landing pad possesses the most easy-to-fail region, which generates up to 50% more entropy compared with the TSV body. …

Optimal Techno-Economic Sizing Of Wind/Solar/Battery Hybrid Microgrid System Using The Forever Power Method, Sami Hamed Alalwani

Masters Theses

"Advancement in power electronics, energy storage, control, and renewable energy sources has led to the use of integrated renewable energy sources in islanded microgrids (MG). Also, the uses of integrated renewable energy sources have become more technically applicable, more economically feasible, and more environmentally friendly than conventional sources. As a result, electrification of rural villages using renewable energy technologies has started to become widely adopted around the world. Since generating power from renewable energy sources is highly intermittent and difficult to predict, the use of proper energy storage technology is important to eliminate mismatches between the load demand and generation. …

A Valuation Model For Two-Stage Contract Negotiations Over Multiple Interdependent Issues, Nnaemeka U. Amaeshi

Masters Theses

"Most real-world negotiation scenarios involve multiple interdependent issues over which the negotiating parties will seek an agreement. Simultaneous negotiation over multiple interdependent issues is an especially challenging problem because utility functions of negotiating agents are typically nonlinear and difficult to analyze. Also, negotiations often happen under circumstances of incomplete information, where either party has either little or inaccurate information about the preferences or utilities of the other party. Consequently, negotiations may go over multiple rounds until a mutually acceptable agreement is reached. The objective of this research is to create a quantitative model of decision-making that helps one negotiating party …

Evaluation Of Nickel-Titanium Oxide-Niobium Pentoxide Metal Ceramic Composite As Interconnect For Solid Oxide Fuel Cell, Abhijith Budur

Masters Theses

"With increasing importance for clean energy, fuel cells have gained great significance in recent decades. Solid oxide fuel cells are easy to transport due to presence of solid electrolyte and also have requisite electrical properties,but have been obstructed by their limitation to be used at only temperatures greater than 600⁰C and less than 800⁰C. To construct a stack of cells, materials that are good electrical conductors and having necessary mechanical strengths at that temperatures are being considered as interconnects between the cells. Evaluation of Nickel-Titanium dioxide-Niobium pentoxide (NTN) as interconnect and comparison to Stainless Steel 441 alloy has been made …

Ph Dependent Antibiotic Resistance Of An Alkaliphilic, Halotolerant Bacterium Isolated From Soap Lake, Washington, Tiffany Charlynn Edwards

Masters Theses

"Soap Lake, located in Washington State, is a meromictic, soda lake. Many bacterial isolates retrieved from Soap Lake have been noted to possess resistance to multiple antibiotics. A likely explanation for the wide range of antibacterial resistance exhibited by these strains is due to the impact of high alkalinity on the antibiotics themselves and not due to the presence of antibiotic resistance genes. The aim of our study was to determine if select antibiotics are effective against Halomonas eurialkalitoleranis, a bacterium capable of growth over a wide range of neutral to alkaline pH values, to investigate the influence of alkalinity …

Adjoint-Based Airfoil Shape Optimization In Transonic Flow, Joe-Ray Gramanzini

Masters Theses

"The primary focus of this work is efficient aerodynamic shape optimization in transonic flow. Adjoint-based optimization techniques are employed on airfoil sections and evaluated in terms of computational accuracy as well as efficiency. This study examines two test cases proposed by the AIAA Aerodynamic Design Optimization Discussion Group. The first is a two-dimensional, transonic, inviscid, non-lifting optimization of a Modified-NACA 0012 airfoil. The second is a two-dimensional, transonic, viscous optimization problem using a RAE 2822 airfoil. The FUN3D CFD code of NASA Langley Research Center is used as the ow solver for the gradient-based optimization cases. Two shape parameterization techniques …