Digital Commons Network^™

Investigation Of Decoupling Capacitor Connection Methods Using Peec And Study Of Alien Crosstalk From A Broadr-Reach® Protocol Based System, Tamar Makharashvili

Masters Theses

"Power Distribution Network (PDN) for Printed Circuit Board (PCB) design requires proper power integrity analysis. In order to deliver a low-ripple DC voltage from a Voltage Regulator Module (VRM) to an Integrated Circuit (IC), a certain target input impedance should be achieved. Developing simple physics-based equivalent circuit models are essential for understanding how a system works and making crucial design decisions. In this work, the input impedance of a decoupling capacitor due to traces, pads and via discontinuities are investigated using the Physics-based Model Size Reduction (PMSR) method. Various decoupling capacitor connection methods are compared and design guidelines are provided …

A Sentence-Based Image Search Engine, Weizhi Meng

Masters Theses

"Nowadays people are more interested in searching the relevant images directly through search engines like Google, Yahoo or Bing, these image search engines have dedicated extensive research effort to the problem of keyword-based image retrieval. However, the most widely used keyword-based image search engine Google is reported to have a precision of only 39%. And all of these systems have limitation in creating sentence-based queries for images.

This thesis studies a practical image search scenario, where many people feel annoyed by using only keywords to find images for their ideas of speech or presentation through trial and error. This thesis …

Design And Implementation Of A Broker For Cloud Additive Manufacturing Services, Venkata Prashant Modekurthy

Masters Theses

"The growing number of cloud Additive Manufacturing (AM) services, offered by different providers over the Internet, makes it challenging for consumers to compare these cloud AM services to select a service of their choice. In addition, it is even more challenging for consumers to compare these cloud AM services against their personal preferences. This is because, consumers personal preferences on multiple service attributes such as price, material, accuracy, and schedule, should be considered for cloud AM service selection. The decentralized nature of these cloud AM services coupled by the need to consider consumers personal preferences during cloud AM service selection, …

Studies On The Role Of Organic-Inorganic Hybrid Polyacrylamides In Fine Coal Flotation, Ontlametse Kenneth Molatlhegi

Masters Theses

"The current study investigated the effect of novel organic/inorganic (hybrid) polyacrylamide polymer as ash (slimes) depressant in fine coal flotation for the possibility to enhance the combustible recovery and ash rejection. Raw coal samples contain about 25% of ash-forming minerals were crushed, grinded to -75um and floated in the presence of in-house synthesized hybrid Polyacrylamide (Al(OH)₃-PAM or Al-PAM) at different operational parameters. Denver flotation cell with a 5-Liters capacity was used and the parameters investigated include: Al-PAM dosage, Al-PAM conditioning time, dual use of Al-PAM and a dispersant, impeller rotation speed and pulp's pH. For comparison purposes, commercially …

Detection And Cancellation Of Sinusoidal Fading Power Variation In Wireless Communication Systems, Sushruth Sastry

Masters Theses

"Fading channel estimation in wireless communication systems depends on an expected model for fading and any assumptions made about the channel itself. The bit error rate (BER) performance of the communication system is affected by how closely these assumptions made in designing the estimation technique match the deployment environment. Any unforeseen disturbances or hindrances in the environment deteriorate the BER performance of the system when the estimation system is not designed to combat such disturbances. To deal with such unforeseen obstacles, additional mathematical models can be proposed to model such disturbances and then the estimation techniques can either be reinforced …

A New Equivalent Dipole-Moment Source Reconstruction Method For Ic Radiated Emissions Based On Near-Field Scanning, Xiao Ren

Masters Theses

"In this paper, a new dipole-moment model based on near-field scanning for representing equivalent IC radiation emissions on a PCB (Print Circuit Board) is presented. One set of dipoles (both electric dipoles and magnetic dipoles) are used to characterize near-field and far-field radiation from the source. In order to build the model, tangential electric field and magnetic field on a Huygens's box enclosing the radiation source are needed. Both the phase and magnitude of these tangential fields are obtained either in simulation or in measurement by near-field scanning method. Two steps are established to reconstruct the dipole moment. Firstly, a …

Advanced Sustainable Concrete Materials For Infrastructure Applications, Kaylea Ann Smith

Masters Theses

"This study was performed to examine the effects of cement replaced by high volumes of Class C fly-ash on durability characteristics of concrete up to 120 days. Specifically, this study investigates possibility of amending American Society for Testing and Materials (ASTM) to allow High Volume Fly-ash (HVFA) concrete to cure until later ages prior to testing instead of 28 days. Five mix designs were compared with varying fly-ash percentages from 0 to 70% (by total cementitious mass). No other additives were present in any of the five mix designs. Water-to-cementitious ratio (w/cm) and total cementitious material remained constant as 0.40 …

Freeform Extrusion Fabrication Of Titanium Fiber Reinforced 13-93 Bioactive Glass Scaffolds, Albin Thomas

Masters Theses

"Although implants made with bioactive glass have shown promising results for bone repair, their application in repairing load-bearing long bones is limited due to their poor mechanical properties as compared to human bones. This thesis study is on freeform extrusion fabrication of silicate based 13-93 bioactive glass scaffolds reinforced with titanium fibers. A composite paste was prepared with 13-93 bioactive glass filled with titanium fibers (~16 µm in diameter and aspect ratio of ~250) having 0.1 to 0.4 vol. % of the bioactive glass scaffold. This paste was then filled into a syringe manually, and then extruded through a nozzle …

A Geochemical Investigation Of Co₂ Sequestration And Site Characterization At Two Missouri Locations, Robert Allen Swain

Masters Theses

"The feasibility of sequestering CO₂ in saline aquifers of Lamotte Formation sandstone was investigated at wells located near Thomas Hill power plant, Moberly, MO and Sioux City Power Plant in Florissant, MO. Governing factors of using aquifers for CO₂ disposal include water salinity, potential for carbonic acid buffering, rate of precipitation of carbonate minerals following CO₂ introduction into the host aquifer, and the integrity of the Davis and Derby-DoeRun shale as a trap rock to prevent migration of the CO₂ phase and carbonic acid into the overlying potable Ozark Aquifer.

Both in situ and laboratory methods …

A Subband Kalman Filter For Echo Cancellation, Rakesh Vijayakumar

Masters Theses

"This thesis involves the implementation of a Kalman filter for the application of echo cancellation. This particular Kalman filter is implemented in the frequency domain, in subbands, so as to make it faster and of lesser calculational complexity for real time applications. To evaluate the functioning of this subband Kalman filter, comparison of the performance of the subband Kalman filter is done with respect to the original time domain Kalman filter, and also with other subband adaptive filters for echo cancellation such as the NLMS filter. Additionally, since background noise affects the working of any adaptive filter, the newly developed …

Uncertainty Quantification Of Turbulence Model Closure Coefficients For Transonic Wall-Bounded Flows, John Anthony Schaefer

Masters Theses

"The goal of this work was to quantify the uncertainty and sensitivity of commonly used turbulence models in Reynolds-Averaged Navier-Stokes codes due to uncertainty in the values of closure coefficients for transonic, wall-bounded flows and to rank the contribution of each coefficient to uncertainty in various output flow quantities of interest. Specifically, uncertainty quantification of turbulence model closure coefficients was performed for transonic flow over an axisymmetric bump at zero degrees angle of attack and the RAE 2822 transonic airfoil at a lift coefficient of 0.744. Three turbulence models were considered: the Spalart-Allmaras Model, Wilcox (2006) k-ω Model, and the …

The Impact Of A Strong Local Supply Chain On Regional Economic Impacts Of Mining, Meiyu Xing

Masters Theses

"With growing social conflicts due to social and environmental concerns mines need to be able to create shared value for all stakeholder in their quest to promote sustainable development. Given the sensitivity of a mine's regional economy contribution to its supply chains, any improvement in supply chains strategy will be beneficial for mines and their stakeholders. The objectives of this work were to: (i) test the hypothesis that supply chain management strategy, by mines in a region, significantly affects regional economy; and (ii) develop a methodology to identify the critical backward commodities of a regional mining sector.

Valid methods have …

Shear-Friction Of Sand-Lightweight Clay And Slate Aggregate Concretes With Varied Reinforcement Ratios, Samantha Lynn Wermager

Masters Theses

"This thesis focuses on the structural properties of sand-lightweight aggregate concrete in terms of shear transfer strength at cold-joint interfaces. This type of interface is common for precast concrete connections which are typically designed using the shear-friction concept. This testing program was meant to expand the shear-friction database and evaluate the appropriateness of current shear-friction design provisions with respect to sand-lightweight concrete. This study builds on the work done by Shaw (2013) who studied lightweight expanded shale aggregate concrete. The current study included thirty-two push-off specimens constructed from sand-lightweight concrete with a target compressive strength of 5,000 psi. Either expanded …

Steam Flooding Screening And Eor Prediction By Using Clustering Algorithm And Data Visualization, Na Zhang

Masters Theses

"Enhanced Oil Recovery (EOR) techniques are vitally important in the oil industry because these techniques could not only extend the life of wells, but also produce 10% to 30% additional oil from the reservoir. However, selecting the most suitable EOR techniques for unknown reservoirs is not easy for decision making. Based on literature, EOR screening criteria could help to find the best candidates for unknown projects, which is classified into two categories: conventional EOR screening and advanced EOR screening. In this research, an artificial intelligent (AI) method, hierarchical clustering algorithm, is adapted to analyze both steam flooding projects and worldwide …

Paleogeographic And Paleoenvironmental Evolution Of Lacustrine And Fluvial Upper Triassic Zhangjiatan Shale Sequence, Ordos Basin, China, Qiuwan Yu

Masters Theses

"Detailed sequence stratigraphic and depositional systems analyses can effectively delineate factors and processes controlling deposition of fine-grained lacustrine sediments. Upper Triassic Zhangjiatan (ZJT) Shale Bed and adjacent strata in Ordos foreland basin was used as an example. A new depositional sequence model shows that the maximum regressive shoreline was more landward than that at the lowest lake-level. The study area is on the ramp margin, covering 100x90 km². Thin sections, cores and well-logs of 80 wells are used to calibrate log signatures, document lithofacies, and interpret depositional facies in a sequence stratigraphic context. The entire sequence thickens from …

Survey And Data Analysis Of Polymer Flooding Pilot And Field Applications In China, Yandong Zhang

Masters Theses

"Enhanced oil recovery (EOR) processes are regarded as important methods to recovery remaining oil after primary and secondary recovery. It is significant to select the most appropriate EOR process among the possible techniques for a candidate reservoir. EOR screening criteria has been created using available EOR datasets and served as the first step to compare the suitability of each EOR method for a particular reservoir. Most of these datasets are collected from EOR surveys published by Oil & Gas Journal. This study proposes a comprehensive study of a dataset including 55 pilot and field polymer flooding applications in China. Statistical …

Methods For Checking And Enforcing Physical Quality Of Linear Electrical Network Models, Mikhail Zvonkin

Masters Theses

"Most CAD tools allow system-level simulation for signal integrity by computing and connecting models together for the various sub-parts. The success of this model derivation depends on the quality of the network parameters. Different errors may seriously affect the quality of the frequency characterization: frequency-dependent measurement errors, errors due to the numerical simulation and/or discretization, etc. When these errors are large, model assembly and simulation becomes difficult and may even fail. This thesis gives an overview of the most significant properties of physically valid network parameters, describes existing methods for checking and enforcing these properties, and presents several new methodologies …

Productivity And Efficiency Impacts Of Urea Deep Placement Technology In Modern Rice Production: An Empirical Analysis From Bangladesh, S Rahman, Bk Barmon

School of Geography, Earth and Environmental Sciences

Rice is the most dominant field crop in Bangladesh covering 75% of the total cultivated area and consumes 80% of the total fertilizers alone. Nevertheless, the productivity of rice in Bangladesh remains one of the lowest in the world. Urea, the main source of nitrogen (N), plays a key role in rice production, is required in large amount, is the most limited nutrient and also suffers from heavy system losses. A worldwide crisis of urea fertilizer in 2008 spurred the need to economise on its use with urgency. The Urea Deep Placement (UDP) technology is aimed at increasing N fertilizer …

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 …

Numerical Study Of Upstream And Downstream Regions Of One Dimensional Detonation Wave In A Dusty Gas Medium, Shubhadeep Banik

Masters Theses

"In detonative combustion very high temperatures are attained by the burned gases. As a result, a large amount of thermal energy is produced during the combustion process. This heat can affect the state of the unburned fuel through radiation of heat from the burned gases. In this study a one-dimensional model was deemed appropriate to gain insight into the fundamental structure of the detonation wave. In this model, the detonation wave divides the fluid stream into an upstream region, consisting of fuel and oxidant, and a downstream region, consisting of burned gases. A set of computer programs, some developed during …

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 …

Argumentation Based Collaborative Software Architecture Design And Intelligent Analysis Of Software Architecture Rationale, Nagaprashanth Chanda

Masters Theses

"A growing model for software architecture defines it as a set of principle design decisions which drive system architects to design the architecture satisfying software requirements and architectural constraints. The design decision making process involves a group of stakeholders exchanging their viewpoints to address various concerns and to reach a consensus collaboratively. These architecture design decisions are usually made based on experiences since there aren't defined methods and models for architecture design. Each design decision yields a set of outcomes which impacts both the system architecture and the final product. As software product systems, tend to be large in size, …

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 …

Neutronic Analysis Of Light Water Small Modular Reactor With Flexible Fuel Configurations, Brendan Dsouza

Masters Theses

"The study was focused on the analysis of light water Small Modular Reactor (SMR) with flexible fuel configurations. The core design, based on the Westinghouse UO₂ SMR with less than 5% enrichment was developed using the Monte Carlo N-Particle (MCNP) code. Neutronics analyses of a reference core with UO₂ fuel was performed to characterize parameters such as the radial neutron flux profile, the maximum to average flux ratio, the reactivity coefficient and critical boron concentration at beginning of life; which confirmed good performance in comparison to a standard UO₂ based pressurized water reactor.

Using this uranium oxide …

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 …

Nanoscale Mechanical Switching Of Ferroelectric Polarization Via Flexoelectricity, Yijia Gu, Zijian Hong, Jason Britson, Long-Qing Chen

Materials Science and Engineering Faculty Research & Creative Works

Flexoelectric coefficient is a fourth-rank tensor arising from the coupling between strain gradient and electric polarization and thus exists in all crystals. It is generally ignored for macroscopic crystals due to its small magnitude. However, at the nanoscale, flexoelectric contributions may become significant and can potentially be utilized for device applications. Using the phase-field method, we study the mechanical switching of electric polarization in ferroelectric thin films by a strain gradient created via an atomic force microscope tip. Our simulation results show good agreement with existing experimental observations. We examine the competition between the piezoelectric and flexoelectric effects and provide …

Teaching Unincorporated Business Associations Through A Simulated Start-Up, Brett Mcdonnell

Articles

This paper describes the Unincorporated Business Associations course taught by the author. The course is organized around a simulated start-up LLC. Students are assigned roles as counsel for one of the founders of the simulated LLC. Over a series of four exercises, students negotiate and draft the provisions of an operating agreement. The course both helps develop important practice skills such as negotiating and drafting, but more fundamentally helps students understand the law of business associations through understanding how that law provides background legal rules for drafting the terms of individual agreements.

Directional Thermal Emission From A Leaky-Wave Frequency-Selective Surface, Edward C. Kinzel, J. C. Ginn, L. A. Florence, B. A. Lail, G. D. Boreman

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.

Stochastic Interdigitation As A Toughening Mechanism At The Interface Between Tendon And Bone, Y. Hu, Victor Birman, A. Demyier-Black, A. G. Schwartz, S. Thomopoulos, G. M. Genin

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.