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Masters Theses

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Effect Of Web Atmospheric Cues On Users' Emotional Responses In Ecommerce, Tanvi Joginapelly Jan 2011

Effect Of Web Atmospheric Cues On Users' Emotional Responses In Ecommerce, Tanvi Joginapelly

Masters Theses

"The internet has revolutionized the shopping experience. As consumers' emotional responses play an important role in predicting behavioral intentions and satisfaction, it is imperative to study e-commerce from an affective perspective and identify the website design features that influence consumers' emotional responses. This research adopted the stimulus-organism-response (S-O-R) model to examine the effects of web atmospheric cues. mainly vividness and interactivity, on users' emotional responses in e-commerce, and their influence on users' purchasing intentions.

The study had three stages: First, experts in human computer interaction (HCI) were recruited and asked to evaluate and rate 25 different e-commerce websites on interactivity …


Bi-Harmonic Atomic Force Microscopy, Santosh R. Kodandarama Jan 2011

Bi-Harmonic Atomic Force Microscopy, Santosh R. Kodandarama

Masters Theses

"In tapping mode atomic force microscopy, surface features are measured indirectly via the amplitude of the tapping cantilever. A change in surface profile is detectable only if it results in an amplitude change that is significant enough to be measured by the optics. Previous works have focused on improving sensitivity through the system's Q-factor, either by changing physical cantilever properties or using feedback control, but those approaches undesirably slow down the dynamic response. In this work we take a novel approach to sensitivity amplification by reshaping the tapping trajectory. By shaping the trajectory so that the probe spends a greater …


Multiple-Input Multiple-Output System Simulation For Spinning Vehicles, Samuel James Petersen Jan 2011

Multiple-Input Multiple-Output System Simulation For Spinning Vehicles, Samuel James Petersen

Masters Theses

"This paper investigates the performance of a multiple-input multiple-output (MIMO) wireless communication system, when the transmitter is located on a spinning vehicle. In particular, a 2x2 MIMO system is used, with Alamouti coding at the transmitter. Both Rayleigh and Rician statistical models are considered in this paper and are combined with a deterministic spinning model to simulate the channel. The spinning of the transmitting vehicle, relative to the stationary receive antennas causes additional signal fading, and complicates the decoding and channel estimation. The simulated bit error rate is the primary performance metric used. A 4x2 asymmetric Alamouti coding scheme is …


Crack Formation In Investment Casting Ceramic Shells, W. A. Everhart Jan 2011

Crack Formation In Investment Casting Ceramic Shells, W. A. Everhart

Masters Theses

"This thesis is a collection of papers that discuss shell cracking in investment casting during pattern removal. The application of rigid polymeric foam for large investment casting patterns with complex geometries can improve the dimensional tolerances and the surface quality of the casting. However, these pattern materials have a tendency to promote crack formation in investment casting shells during pattern removal by firing.

The first two papers discuss the factors affecting shell cracking and methods to prevent it. Experimental methods were combined with finite element modeling to predict stress in the shell. A 3D nonlinear finite element model was developed …


A Neural Network Based Approach For Path Planning On Costmap, Songjie Chen Jan 2011

A Neural Network Based Approach For Path Planning On Costmap, Songjie Chen

Masters Theses

"In this thesis, a path planning method using a three-level hierarchical system model is proposed. In the top level of the hierarchy, the given location points to visit are taken as waypoints. The waypoint navigation process is formulated as a traveling salesman problem (TSP). The Lin-Kernighan algorithm is used to solve the TSP and transfer the solution to the lower level of the hierarchy. In the middle level, the path is represented by a grid-based costmap. A novel modified Grossberg neural network is designed to solve the point-to-point path planning. The bottom level of the hierarchy smoothens the path with …


Influence Of Particle Size And Specimen Preparation On The Iowa Pore Index, Christopher Paul Davis Jan 2011

Influence Of Particle Size And Specimen Preparation On The Iowa Pore Index, Christopher Paul Davis

Masters Theses

"This study was performed in order to identify a size correction that would allow aggregate of different sizes, other than the standard 1/2-3/4-inch fraction, to be used in the Iowa Pore Index (IPI) test. This size correction would allow for the IPI to be determined for aggregate gradations of material that have a nominal maximum size (NMS) smaller than 3/4-inch. The interest in a size correction for the IPI developed from its use in a Durability Factor (DF) estimation equation. The estimation equation was developed with the use of 19 different DF from Missouri aggregate sources, where eight aggregates had …


Assess Commercialization Feasibility Of Algae-Based Bio-Fuel With Dashboard And Scorecard Technologies, Madhur Chopra Jan 2011

Assess Commercialization Feasibility Of Algae-Based Bio-Fuel With Dashboard And Scorecard Technologies, Madhur Chopra

Masters Theses

"The growing energy depleting energy supplies and increasing environmental pollution has motivated researchers across the globe to look for alternative energy sources. Various energy sources have been identified but none of them have the capability of realistically replacing the fossil fuels and meeting the current demand. Algae based bio-fuels give some hope but producing them at large scale is a challenge which needs to be overcome.

The underlying objective of this research project is two folds. Firstly, the project aims to assist with the commercialization of algae based bio-fuels by developing Dashboard based and Balanced Scorecard based monitoring prototypes. The …


Towards On-Line Voltage Stability Assessment Using Synchrophasors, Himanshu Subandhu Hirlekar Jan 2011

Towards On-Line Voltage Stability Assessment Using Synchrophasors, Himanshu Subandhu Hirlekar

Masters Theses

"Voltage instability has become a growing concern in the operation of power systems in recent years. The reason is that power systems all over are being operated with reduced margins because of increased demand exacerbated by a general reluctance to invest in improvement of the electric grid infrastructure. Until recently it was difficult to predict voltage instability in the on-line environment. However, advances in technology has made possible the on-line monitoring and assessment of voltage stability. Synchrophasors is a relatively new technology in the field of power systems which allows system operators to monitor the system conditions at specific measurement …


Uncertainty Quantification Integrated To Computational Fluid Dynamic Modeling Of Synthetic Jet Actuators, Srikanth Adya Jan 2011

Uncertainty Quantification Integrated To Computational Fluid Dynamic Modeling Of Synthetic Jet Actuators, Srikanth Adya

Masters Theses

"The Point Collocation Non-Intrusive Polynomial Chaos (NIPC) method was applied to a stochastic synthetic jet actuator problem to demonstrate the integration of computationally efficient uncertainty quantification to the high-fidelity CFD modeling of Synthetic Jet Actuators. The uncertainty quantification approach was first implemented in two stochastic model problem cases for the prediction of peak exit plane velocity using a Fluid Dynamic Based analytical model of the Synthetic Jet Actuator, which is computationally less expensive than CFD simulations. The NIPC results were compared with direct Monte Carlo sampling results. To demonstrate the efficient uncertainty quantification in CFD modeling of synthetic jet actuators, …


Mutual Attraction Guided Search: A Novel Solution Method To The Traveling Salesman Problem With Vehicle Dynamics, Jared Adam Nisbett Jan 2011

Mutual Attraction Guided Search: A Novel Solution Method To The Traveling Salesman Problem With Vehicle Dynamics, Jared Adam Nisbett

Masters Theses

"Traveling Salesman Problem (TSP) solution techniques are often used for route planning for automated vehicles. Most TSP solution methods focus on path length as the fitness reference, however in many cases, traversal time is of more practical importance. Mutual Attraction Guided Search (MAGS) is a novel solution method that uses an iterative process to simultaneously optimize both angle of travel through each target as well as the ordering of the targets in order to optimize path traversal time. MAGS deterministically locates a locally optimum solution quickly and can optimize for the acceleration limits of a specific vehicle rather than requiring …


Numerical Simulation Of Relative Permeability Modifier Effect On Oil And Water Production, Murad Mohammedahmed Abdulfarraj Jan 2011

Numerical Simulation Of Relative Permeability Modifier Effect On Oil And Water Production, Murad Mohammedahmed Abdulfarraj

Masters Theses

"Excess water production is one of the most prevalent operational problems that oil companies are facing. Polymers and polymer gels have been used widely to control excess water production for mature oilfields. It is well known that polymers/gels can reduce the permeability to water (Krw) much more than that to oil (Kro). This phenomenon is called disproportionate permeability reduction (DPR) and the polymers or gels that exhibit this behavior are called relative permeability modifier (RPM). When RPMs are placed in reservoir, reduced permeability to water can lead to decreased water production, and sometimes increased hydrocarbon production, therefore prolonging the useful …


Model Based Diagnostics And Prognostics Of Practical Industrial Systems, Raja Sekhar Kraleti Jan 2011

Model Based Diagnostics And Prognostics Of Practical Industrial Systems, Raja Sekhar Kraleti

Masters Theses

"In this thesis, the diagnosis and prognosis of single and simultaneous multiple incipient faults in practical industrial systems is demonstrated in two papers. For the purpose of fault detection and failure prediction, a model based strategy is adopted, which involves using an online adaptive estimator. The online estimator estimates the system dynamics. Residual is generated based on the physical system model and the estimated system dynamics. This residual is used to detect the fault. Once the fault is detected, a tunable nonlinear neural network online approximator in discrete-time (OLAD) along with a robust adaptive term is initiated. The OLAD utilizes …


Relaxation Imaging To Characterize Lightweight Polymer-Crosslinked Aerogels, Emmalou T. Satterfield Jan 2011

Relaxation Imaging To Characterize Lightweight Polymer-Crosslinked Aerogels, Emmalou T. Satterfield

Masters Theses

"Silica aerogels are three-dimensional assemblies of silica nanoparticles with extremely low densities. In some instances, the internal void volume is more than 90% of the total volume. The highly porous structure of the aerogels leads to attractive properties for thermal and noise insulation, due to very low thermal conductivity and very high acoustic impedance. The strength of silica aerogels has been substantially improved by casting a thin conformal polymer coating over the entire internal porous surfaces of the nanostructure. The coating reinforces the interparticle connections without significantly compromising the internal void space. To analyze and compare the properties of several …


The History Of Technical Communication Instruction At Missouri University Of Science And Technology: The Evolution Of A Curriculum, Elizabeth Marie Roberson Jan 2011

The History Of Technical Communication Instruction At Missouri University Of Science And Technology: The Evolution Of A Curriculum, Elizabeth Marie Roberson

Masters Theses

"This thesis provides a written record of the history of technical communication instruction at Missouri University of Science and Technology (Missouri S&T). Beginning with the school's inception in 1871 as the Missouri School of Mines and Metallurgy (MSM) through to the year 2005, I have examined course catalogs and department files and conducted interviews to provide an overview of the evolution of technical communication instruction at this institution. To better understand this evolution, I have also provided a framework for the development of the English department from a single course in 1871 to the current Department of English and Technical …


Inherent And Model-Form Uncertainty Analysis For Cfd Simulation Of Synthetic Jet Actuators, Daoru Frank Han Jan 2011

Inherent And Model-Form Uncertainty Analysis For Cfd Simulation Of Synthetic Jet Actuators, Daoru Frank Han

Masters Theses

"A mixed aleatory (inherent) and epistemic (model-form) uncertainty quantification (UQ) analysis method was applied to a computational fluid dynamics (CFD) modeling problem of synthetic jet actuators. A test case, (Case 3, flow over a hump model with synthetic jet actuator control) from the CFDVAL2004 workshop was selected to apply the Second-Order Probability framework implemented with a stochastic response surface obtained from Quadrature-Based Non-Intrusive Polynomial Chaos (NIPC). Three uncertainty sources were considered: (1) epistemic uncertainty in turbulence model, (2) aleatory uncertainty in free stream velocity and (3) aleatory uncertainty in actuation frequency. Uncertainties in both long-time averaged and phase averaged quantities …


Driven Pile Load Test Data For Load And Resistance Factor Design In Missouri, Joseph Ronson Cravens Jan 2011

Driven Pile Load Test Data For Load And Resistance Factor Design In Missouri, Joseph Ronson Cravens

Masters Theses

"The Missouri Department of Transportation (MoDOT) has recently migrated from allowable stress design (ASD) to load and resistance factor design (LRFD) of driven piles. This transition was initiated when the Federal Highway Administration (FHWA) issued a policy stating that all new bridge designs shall be designed in accordance with the American Association of State Highway and Transportation Officials (AASHTO) LRFD Bridge Design Specifications to eliminate the difference in design methodologies for bridge superstructures and bridge substructures. However, the resistance factors for driven piles specified in the AASHTO LRFD specifications are based on nationwide pile data, consisting of a wide range …


Educational Robotics: Using The Lego Mindstorms Nxt Platform For Increasing High School Stem Education, Matthew Aaron Strautmann Jan 2011

Educational Robotics: Using The Lego Mindstorms Nxt Platform For Increasing High School Stem Education, Matthew Aaron Strautmann

Masters Theses

"The field of educational robotics (ER) seeks to use the building and programming of robots to engage and educate the next generation of college freshman entering science and engineering majors. To increase the rate of application to science and engineering degree programs as well as the rate of retention, students must be engaged in high school. They must acquire the knowledge and interest to pursue these career choices. This research explores the use of robotics to interest high school students in science, technology, engineering, and math (STEM) and to improve their knowledge of these subjects. The case study developed instructional …


Isolation And Characterization Of Bacterial Symbionts From Crotalaria Spectabilis Grown On Trichloroethene Contaminated Soil, April Lyn Rocha Jan 2011

Isolation And Characterization Of Bacterial Symbionts From Crotalaria Spectabilis Grown On Trichloroethene Contaminated Soil, April Lyn Rocha

Masters Theses

"The discovery of several members of the Leguminosae family growing on a TCE contaminated site demonstrated that they have the capabilities to tolerate the TCE contamination. This led to an investigation of the plants' ability to metabolize TCE. Research by Dr. Lee Newman showed that nodules from Crotalaria spectabilis grown on the site had TCE metabolites present while nodules from other legumes at the site did not. The presence of TCE metabolites within the C. spectabilis nodules suggests that the bacterial symbiont may be responsible for TCE metabolism. This led us to investigate the symbiont of C. spectabilis and its …


Risk-Sensitive Preventive Maintenance Policies Using Semivariance, Venkata Manojramam Tirumalasetty Jan 2011

Risk-Sensitive Preventive Maintenance Policies Using Semivariance, Venkata Manojramam Tirumalasetty

Masters Theses

"Preventive maintenance is an important tool that increases the reliability of the production system by reducing downtime due to failures. In the literature, maintenance and replacement policies for productions systems have been widely studied and modeled. Traditionally preventive maintenance has focused only on minimizing expected costs without considering variability in costs. Cost variability is also commonly known as risk. In a 2003 paper, Chen and Jin used variance of costs as a measure of risk for formulating preventive maintenance policies. The variance criterion that they used ignored the probability of costs exceeding monthly or yearly budgets provided to managers. The …


Experimental Investigation Of Cutting Forces, Temperature And Surface Roughness In End-Milling Of Hastelloy C-2000, Ryan Matthews Jan 2011

Experimental Investigation Of Cutting Forces, Temperature And Surface Roughness In End-Milling Of Hastelloy C-2000, Ryan Matthews

Masters Theses

"This thesis presents the results of experimental investigation of the effects of cutting parameters (spindle speed, feed per tooth, axial depth of cut and radial depth of cut) on the three components of cutting forces (Fx, Fy, Fz), workpiece temperature and surface roughness in end-milling of Hastelloy C-2000 alloy using design of experiments (DOE) and response surface methodology (RSM). End-milling experiments were conducted using 0.5 inch diameter end-mill on Cincinnati Milacron Sabre 750 vertical machining center using water based flood coolant. An inscribed central composite design of experiment was used to study the four …


Development Of A Graphical User Interface For The Study Of Parallel-Connected Solar Arrays, Nisha Nagarajan Jan 2011

Development Of A Graphical User Interface For The Study Of Parallel-Connected Solar Arrays, Nisha Nagarajan

Masters Theses

"For any solar array it is necessary to be able to harness the maximum possible power from it. A new technology is proposed to improve the efficiency of solar arrays and harness maximum potential power as well by connecting the solar panels in parallel. This thesis describes the development of a graphical user interface for the evaluation of this parallel-connected solar array technology and to compare different scenarios for solar arrays to predict the potential power output to decide the best configuration for an application. This is done via several computations and analysis of field data. The first paper describes …


Social Network Analysis Of The Video Bloggers' Community In Youtube, Anusha Mogallapu Jan 2011

Social Network Analysis Of The Video Bloggers' Community In Youtube, Anusha Mogallapu

Masters Theses

"This research studied the structure of the social network of the video blogger community on YouTube. It analyzed the social network structure of friends and subscribers of the 187 video bloggers on YouTube and calculated the social network measures. This thesis compares the results to the structure described by Warmbrodt et al. in 2007 and explains the reasons for the distinctions. The number of video bloggers has increased enormously, and the form of their interactions has changed. As a result, the video blogger social network has evolved from a core/periphery structure to one that is centralized. This indicates that the …


An Incentive Based Approach To Detect Selfish Nodes In Mobile P2p Network, Hemanth Meka Jan 2011

An Incentive Based Approach To Detect Selfish Nodes In Mobile P2p Network, Hemanth Meka

Masters Theses

"The growth of mobile devices led to the wide use of Mobile P2P networks. These networks are used in a wide variety of areas and hence there is lot of research in the field of mobile networks. Detecting selfish nodes is one of the research topics triggered due to the popularity of mobile P2P networks. It is necessary to detect selfish nodes in such networks to improve the efficiency of the network. In this thesis, an incentive based approach to detect selfish nodes is designed and evaluated. This approach differs from the existing work as it (i) can be used …


Longitudinal Evaluation Of A Learning System For Teaching Geographical Information System Within The Context Of A Geotechnical Problem, Aparna Sukhavasi Jan 2011

Longitudinal Evaluation Of A Learning System For Teaching Geographical Information System Within The Context Of A Geotechnical Problem, Aparna Sukhavasi

Masters Theses

"A learning system, to train civil engineering students to apply Geographical Information Systems (GIS) in geotechnical problems, was evaluated over a period of 5 years, hence longitudinal. The system was tested with a series of iterations consisting of usability tests and subsequent modification, which were followed by a series of applied evaluations within the context of class lab sessions. The principal goals of this evaluation were to determine the overall effectiveness of the system and the factors that affected student learning. The first evaluation was conducted in 2004; and included a control group that played a "game" related to the …


Characterization Of Shielding Effectiveness For Metallic Enclosures, Nicholas Bennett Mentesana Jan 2011

Characterization Of Shielding Effectiveness For Metallic Enclosures, Nicholas Bennett Mentesana

Masters Theses

"This topic discusses and verifies an equation for estimating the shielding effectiveness of metallic enclosures through the use of numerical simulations. Using ideas from Bethe's "Theory of Diffraction by Small Holes", a previous student from the Missouri S&T Electromagnetic Compatibility Laboratory developed an equation that would yield an envelope prediction for the worst-case EMI from an aperture array backed by an over-moded cavity. Min Li (PhDEE '99) used results from measurements, simulations, and physics-based equations to formulate a simple equation that would predict these EMI levels. The main purpose of this thesis is to revisit this work and determine when …


3-Dimensional Computational Fluid Dynamics Modeling Of Solid Oxide Fuel Cell Using Different Fuels, Sachin Laxman Puthran Jan 2011

3-Dimensional Computational Fluid Dynamics Modeling Of Solid Oxide Fuel Cell Using Different Fuels, Sachin Laxman Puthran

Masters Theses

"Solid oxide fuel cell (SOFC) technology has been of great interest over many years due to its flexibility in using different fuels for operation; including the fundamental fuel i.e. Hydrogen. Various computational and numerical models have been developed along with experimental work to evaluate the performance as well as to identify and overcome the problems faced in the development of SOFC's. In an attempt to achieve efficient operation with respect to design and combined thermal and electrochemical perspective, the main objective of the proposed study is to present a three-dimensional computational model, which will serve as a framework for the …


Quantifying Model Uncertainty Using Measurement Uncertainty Standards, Harsheel Rajesh Shah Jan 2011

Quantifying Model Uncertainty Using Measurement Uncertainty Standards, Harsheel Rajesh Shah

Masters Theses

"Model uncertainty quantification is mainly concerned with the problem of determining whether the observed data is consistent with the model prediction. In real world, there is always a disagreement between a simulation model prediction and the reality that the model intends to represent. Our increased dependence on computer models emphasizes on model uncertainty which is present due to uncertainties in model parameters, lack of appropriate knowledge, assumptions and simplification of processes. In addition, when models predict multi-variate data, the experimental observation and model predictions are highly correlated. Thus, quantifying the uncertainty has a basic requirement of comparison between observation and …


Adaptive Rule-Based Malware Detection Employing Learning Classifier Systems, Jonathan Joseph Blount Jan 2011

Adaptive Rule-Based Malware Detection Employing Learning Classifier Systems, Jonathan Joseph Blount

Masters Theses

"Efficient and accurate malware detection is increasingly becoming a necessity for society to operate. Existing malware detection systems have excellent performance in identifying known malware for which signatures are available, but poor performance in anomaly detection for zero day exploits for which signatures have not yet been made available or targeted attacks against a specific entity. The primary goal of this thesis is to provide evidence for the potential of learning classier systems to improve the accuracy of malware detection.

A customized system based on a state-of-the-art learning classier system is presented for adaptive rule-based malware detection, which combines a …


Meloc - Memory And Location Optimized Caching For Mobile Ad Hoc Networks, Lekshmi Manian Chidambaram Jan 2011

Meloc - Memory And Location Optimized Caching For Mobile Ad Hoc Networks, Lekshmi Manian Chidambaram

Masters Theses

"The advancement of Mobile ad hoc networks (MANET) is tremendous in the field of social and military applications. Caching and Replication are the two common techniques used to improve data access efficiency in Mobile Ad hoc networks. Caching favors data access efficiency by bringing data closer to the source. Existing caching approaches are deficient in reducing the number of cache locations, thus reducing the number of copies, which is needed for many mission critical applications considering safety and security. Conversely, reducing the number of caches should not affect the efficiency of data access. We design an efficient broker based caching …


Simultaneous Measurement Of Temperature And Strain By Three-Section Phase-Shift Long Period Fiber Grating, Hongbiao Duan Jan 2011

Simultaneous Measurement Of Temperature And Strain By Three-Section Phase-Shift Long Period Fiber Grating, Hongbiao Duan

Masters Theses

"Long period fiber gratings (LPFGs) have found many applications as sensors to measure strain, temperature, refractive index and other physical parameters. In various sensing applications, the cross-sensitivity between two parameters, especially the temperature cross-sensitivity, has been a major difficulty to achieve high accuracy measurement. One of the solutions is to develop LPFG sensors for simultaneous, multi-parameter measurements.

In this thesis, three-section phase-shift (PS) LPFGs were fabricated and investigated for simultaneous measurement of temperature and strain. Compared with a two-section PS-LPFG, a three-section PS-LPFG has two deeper resonance sub bands and a larger separation between the two bands. The strain, temperature …