Engineering Commons^™

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 …

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 …

Development Of A Stochastic Model For Performance Characterization Of A Pv/Vrb Microgrid, Kayla M. Speidel

Masters Theses

"Photovoltaic (PV) Microgrids have been proven to be a useful technology in providing an environmentally friendly source of energy when compared to the use of fossil fuels. Accurately characterizing the performance of a microgrid system would ensure that the system is appropriately sized to meet electrical loads without a heavy reliance on diesel generators. A microgrid that is sized properly will reduce the cost of diesel fuel, while also reducing the risk of wasting money on an oversized system. A deterministic model which was created to characterize the performance of PV microgrids based on percent of time generator running was …

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 …

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 …

Thermodynamic And Chemical Kinetic Coupled Modeling For The Determination Of Cyclic Combustion Phasing In Hcci Engines, Krishawn Michele Goodwin

Masters Theses

"Homogeneous charge compression ignition (HCCI) is a low temperature combustion mode that contains great potential for decreasing emissions while increasing efficiency in internal combustion engines. The limitation is in that it is inherently difficult to control based on the lack of an external combustion trigger. This thesis outlines the potential of using the combustion residual species of carbon monoxide as a method of controlling the location of combustion by using data from a computer model. The model is a nonlinear five-state thermodynamic model that is coupled with a skeletal chemical kinetic model for PRF96. The model computes the amount of …

The Dynamic Behavior Of A Solid State Transformer (Sst) During Recloser Operation In Distribution Systems, Fahd Amin Hariri

Masters Theses

"Electrical power systems are continuously facing increasing electrical power demand in the last years to meet the requirements of modern life style. In order to satisfy such needs electricity authorities are taking appropriate measures to enhance the performance of power networks. One of the solutions to meet the customer's demands for energy was the trend to use the renewable energy. The increasing use of renewable energy and other distributed generation sources made the electrical grid more complex. Many researches have been carried out to find out solutions to overcome this complexity. One of these researches -- which was on a …

Comparative Study Of Three Types Of Inverters Based On The Output Total Harmonic Distortion, Paterrson Thomas

Masters Theses

"In this thesis, three cases of power electronic inverters are taken into consideration to analyze their performance in terms of total harmonic distortion in their output voltage and output current. Firstly, a single H-bridge inverter is simulated. Staircase switching technique is used to generate the gating pulses for the switches. Only one switch is made to toggle for every half cycle. The fundamental harmonic component of the desired output voltage is considered to be 120 V. Secondly, the same topology is used with a Bipolar PWM gating technique. The switching frequency of the carrier wave is 33*60 Hz. Thirdly, a …

Optimum Acquisition And Processing Parameters For Multichannel Analysis Of Surface Waves Using 3d Electrical Resistivity Tomography As Control, Uchenna Chibuzo Nwafor

Masters Theses

"Multichannel Analysis of Surface Waves (MASW) and Electrical Resistivity Tomography (ERT) data were acquired in the Newburg, Missouri with the goal of determining optimum MASW acquisition parameters. Users of the MASW tool generally state that greater geophone intervals and greater shot-to-receiver offsets provide for more accurate results. The objective was to determine if this "rule of thumb" applies in karst terrain.

ERT data were acquired along four traverses with eighty-four (84) electrodes at five feet spacing with SuperSting R8 Resistivity System using dipole- dipole array. The data were processed using Earth Imager to generate 2-D resistivity inversion and thereafter, Voxler …

The Development Of Near Field Probing Systems For Emc Near Field Visualization And Emi Source Localization, Hui He

Masters Theses

"The objectives of this research are to visualize the frequency dependent electromagnetic field distribution for electromagnetic compatibility (EMC) applications and the radiating source reconstruction on complex shaped electronic systems. This is achieved by combining near field probing with a system for automatically recording the probe position and orientation. Due to the complexity of the shape of the electronic systems of interest, and for utilizing the expertise of the user, the probe will be moved manually not robotically. Concurrently, the local near field will be recorded, associated with the location and displayed at near real time on the captured 3D geometry …

Freeze-Form Extrusion Fabrication Of Boron Carbide, Aaron Scott Thornton

Masters Theses

"Boron carbide is a safe, alternative to beryllium as a material for aerospace structures since it is also light-weight and exhibits high strength. This paper discusses a study of the Freeze-form Extrusion Fabrication (FEF) process to fabricate parts from boron carbide. Process parameters and hardware were modified to fabricate boron carbide specimens free of printed defects. Four-point bending tests were performed to measure the flexural strength of fabricated specimens. Observations of the presence of voids caused by ice crystals in fabricated parts led to further development and characterization of the boron carbide paste used with the FEF process. Additives were …

Common Path Pessimism Removal In Static Timing Analysis, Chunyu Wang

Masters Theses

"Static timing analysis is a key process to guarantee timing closure for modern IC designs. However, additional pessimism can significantly increase the difficulty to achieve timing closure. Common path pessimism removal (CPPR) is a prevalent step to achieve accurate timing signoff. To speed up the existing exhaustive exploration on all paths in a design, this thesis introduces a fast multi-threading timing analysis for removing common path pessimism based on block-based static timing analysis. Experimental results show that the proposed method has faster runtime in removing excess pessimism from clock paths."--Abstract, page iii.

Design And Implementation Of Low Complexity Wake-Up Receiver For Underwater Acoustic Sensor Networks, Ming Yue

Masters Theses

"This thesis designs a low-complexity dual Pseudorandom Noise (PN) scheme for identity (ID) detection and coarse frame synchronization. The two PN sequences for a node are identical and are separated by a specified length of gap which serves as the ID of different sensor nodes. The dual PN sequences are short in length but are capable of combating severe underwater acoustic (UWA) multipath fading channels that exhibit time varying impulse responses up to 100 taps. The receiver ID detection is implemented on a microcontroller MSP430F5529 by calculating the correlation between the two segments of the PN sequence with the specified …

Formation And Evolution Of Spinel In Aluminum Killed Calcium Treated Linepipe Steels, Obinna Adaba

Masters Theses

"Magnesium aluminate (Spinel) inclusions have been observed to cause hook crack in line pipe steels. These inclusions are typically formed during liquid steel processing at the ladle metallurgy furnace (LMF) and subsequently modified by calcium to form less harmful liquid inclusions. Unfortunately, spinel inclusions are still sometimes observed in samples taken from the tundish and coil after calcium treatment.

The formation and evolution of spinel inclusions during liquid steel processing at two industrial mini mills was investigated by analysis of lollipop samples taken at different stages of the steelmaking process. The effect of reoxidation on the formation of spinels after …

Detecting Diesel Particulate Matter Using Real Time Monitoring Under The Influence Of An Exhaust Fan System, Yasir Helal Alghamdi

Masters Theses

"Diesel Particulate Matter (DPM) is a complex mixture of diesel exhaust gas that consists of carbon, ash, metallic abrasion particles, sulfates and silicates. The diesel soot particle includes a solid core made of elemental carbon, and organic carbon compound attached to the surface of the soot particle. The main source of DPM is diesel exhaust gas. The National Institute for Occupational Safety and Health (NIOSH) and the Environmental Protection Agency (EPA) have determined that DPM is the source of most of the emissions of carbon monoxide, carbon dioxide, oxide of nitrogen, and hydrocarbons in underground coal, metal and non metal …

A Decision Support Simulation Model For Bed Management In Healthcare, Raja A. Baru

Masters Theses

"In order to provide access to care in a timely manner, it is necessary to effectively manage the allocation of limited resources such as beds. Bed management is key to the effective delivery of high-quality and low-cost healthcare. An efficient utilization of beds requires a detailed understanding of the hospital's operational behavior. It is necessary to understand the behavior of a hospital in order to make necessary adjustments to its resources, and policies, which can improve patient's access to care. The aim of this research was to develop a discrete event simulation to assist in planning and staff scheduling decisions. …

Performance Metrics For Powder Feeder Systems In Additive Manufacturing, Venkata Sivaram Bitragunta

Masters Theses

"In blown powder Direct Metal Deposition (DMD) process, parts are built by adding metal powder on the melt pool created by the laser system. At low feed rates powder feeder systems have perturbations. The study focused on relationship between the perturbation frequencies by inherent powder feeder designs and its impact on deposition quality. Performance metric determine the relation between perturbations in the powder flow and quality of the deposit. To determine performance metric, various powder feeder designs were analyzed. Perturbation frequencies were introduced to the disk feeder design. The quality of the deposit was determined by the surface roughness of …

An Improved Planar Cavity Model For Dielectric Characterization, Benjamin Jay Conley

Masters Theses

"Accurate characterization of the dielectric properties of the laminate materials used in printed circuit board fabrication is critical for maximizing the performance of modern high speed circuitry. While many techniques exist for characterizing dielectric materials, most existing techniques are either limited in accuracy or highly impractical for use with planar, copper-clad laminate sheets. A common method involves forming a cavity from the printed circuit board material and calculating the permittivity and dissipation factor from the measured resonant frequencies and quality factor of the cavity. This resonance technique makes the assumption of an ideal cavity, which leads to errors in both …

Utilizing Learning Style Preferences And Quality Function Deployment For Curriculum Development, Julie M. Ezzell

Masters Theses

"Workplace requirements continually evolve to keep pace with the developing global market. To meet ever increasing standards, educational institutions have been investigating methods to prepare students for their future employment. Course modifications should be carefully considered to meet the requirements of all stakeholders, including those of the students. The objective of this research was to provide students with an overall better learning experience that tailors the teaching methods to his/her individual learning preferences. To meet this objective, a comprehensive survey was provided to an undergraduate course in quality. The survey documented the student's individuality when learning and made note of …

Synthesis Of Different Sizes & Functions Nanoparticles, Jiaming Geng

Masters Theses

"Nanogels, whose size range from 1 to 100nm, have been interested in many research areas: cosmetics, pharmaceuticals, catalysts, photochemistry, and in optical switches or sensors. In Petroleum Engineering area, nanogels can be used as conformance control agent and emulsion stabilizer. And after grafting functional groups or hybrid, nanogels can be used as tracer for the visual modeling.

Though nanoparticles have been studied for more than 20 years, few of them are about nanogels. In the thesis, stirring rate, surfactant type and concentration were found have a large impact on the synthesis of nanogels. And cationic nanogels have salt and acid …