Digital Commons Network^™

Verifying Module Heuristics For Large Scale Products, Rachel Marie Day

Masters Theses

"Decreasing time and costs is a major objective in many businesses today. Including modularity in the early design phases can effectively decrease time spent on and costs associated with a project. The task of identifying modules within a product early in the design process (when decisions are less expensive) is made less daunting by using the techniques of functional modeling and module heuristics. The two papers that form this thesis discuss the results of the efforts to verify the module heuristics on large products. Observations on needed modifications to the functional modeling technique and original module heuristics are reported along …

Development Of A One Dimensional Subsurface Contaminant Transport Model With Stochastic Applications, Benjamin Waldon Johnson

Masters Theses

"Contaminant source release history is a necessary element of contaminant mass transport simulation in the saturated zone. The source release history is unknown at many sites, and many inverse models have been developed to define finite release histories. To define a likely domain of three source history parameters, a mass balancebased one dimensional approach is developed and tested by discretizing the spatial domain into bands. By incorporating the approach in a spreadsheet model, observed data is represented by both variable length and constant length bands of analysis. Each representation of observed data was tested to determine the most appropriate band …

On-Line Depth Measurement Of Micro-Scale Laser Drilled Holes, Rock Allen Powell

Masters Theses

"A micron-precision micro-hole depth detection scheme has been developed which utilizes a confocal structure and a photomultiplier tube as a photodetector. This scheme is experimentally confirmed to posses an accuracy of greater than 95% for micro-holes on the order of one-hundred microns in diameter and tens of microns in depth and could be easily be integrated for the control of industrial and research oriented laser micro-machining process"--Abstract, page iii.

Exploring The Use Of A Commercial Game Engine For The Development Of Educational Software, Hussain Alafaireet

Masters Theses

"Three-dimensional visualization and simulation environments are becoming increasingly important in both industrial and educational environments. However, developing these simulations can be a difficult and expensive task. Herein we explore the use of a commercial game engine to develop a 3-D, interactive computer game designed to teach players about the anatomy of a frog. The goal of this project is threefold: 1) to develop high-fidelity virtual reality educational software with a limited budget and limited personnel, 2) to define a software development process by which similar simulations can be developed, and 3) to explore the benefits that these simulations provide to …

On The Effects Of Small-Scale Fading And Mobility In Mobile Wireless Communication Network, Bandana Paudel

Masters Theses

"In this study, a comprehensive analysis of the impact of mobility on end-to-end performance measures of Mobile Ad Hoc Network is performed by using small-scale fading models. Network simulation is performed in order to study a wide range of phenomena occurring during MANET communication. The effectiveness of three reactive routing protocols against different level of mobility is observed under varying network parameter like the network size, number of nodes and network connectivity. The study reveals that the network sparseness or density favors one or the other routing mechanism under varying mobility. Outcome of the simulation also provides a great deal …

Localization Of Nodes In Wired And Wireless Networks, Hindu Kothapalli

Masters Theses

"This thesis focuses on the implementation of algorithms for localization of nodes in wired and wireless networks. The thesis is organized into two papers. The first paper presents the localization algorithms based on time of arrival (TOA) and time difference of arrival (TDOA) techniques for computer networks such as the Internet by using round-trip-time (RTT) measurements obtained from known positions of the gateway nodes. The RTT values provide an approximate measure of distance between the gateway nodes and an unknown node. The least squares technique is then used to obtain an estimated position of the unknown node. The second paper …

Development And Evaluation Of An Effective Process For The Recovery Of Oil And Detoxification Of Meal From Jatropha Curcas, Sarthak Gaur

Masters Theses

"There has been significant research on biofuels to ensure national security and economic stability of the US. Jatropha curcas, a hardy plant, holds tremendous potential as a biodiesel source and cattle feed-stock largely due to its high triglyceride and crude protein content. However, its viable economic utilization is limited due to the presence of important toxic compounds, phorbol esters. A novel and efficient process has been developed that obtains high yields of jatropha oil and detoxifies the defatted (oil free) jatropha meal. Principles of solid-liquid extraction were utilized to detoxify the meal and then liquid chromatography was employed to analyze …

Modeling Of Vias And Via Arrays In High Speed Printed Circuit Boards, Arun Reddy Chada

Masters Theses

"This thesis presents modeling approaches for fast calculation of signals in dense via arrays in high speed printed circuit boards (PCBs) and model to hardware correlation study of solid and perforated disk resonators. A 2D finite difference (FD) method to extract the via capacitance which includes the via pad capacitance obtained by solving the laplace equation in the via domain in multi-layer geometries is presented and validated with analytical formulation for via capacitance. Next, closed-form expression for the impedance of an infinitely large parallel plane pair is derived and validated by comparing with cavity model for several numerical examples. The …

Preventing Chemical Product Failure, Kenneth Ombete

Masters Theses

"The purpose of this thesis is to demonstrate a research methodology to prevent chemical product failures. This methodology extends the risk in early design (RED) method for prevention of failure in electromechanical products to include products with chemical subsystems. Inclusion of this domain is demanded by the ever-growing semiconductor and energy industries. The RED method was extended by first identifying principal chemical failure modes and adding them to the failure mode taxonomy. The RED database was then augmented with historical failures of products that included chemical subsystems. Finally, the extension was validated with a case study of a fuel cell"--Abstract, …

Stressed-Eye Analysis And Jitter Separation For High-Speed Serial Links, Nitin Radhakrishnan

Masters Theses

"As the computer and electronics industry moves towards higher data rates, the most important concern in the field of signal integrity is jitter. A data communication link path often consists of a transmitter, a channel, and a receiver. Many mechanisms can contribute to jitter, a timing uncertainty in the received signal. For example, transmitters have intrinsic noise sources that contribute to random jitter and to certain types of deterministic jitter. In addition, external coupling may cause periodic jitter. The bandwidth limitation of the channel also contributes to a fourth type of jitter, inter-symbol interference. This thesis studies the various components …

Numerical Modeling And Analysis Of Complex Electromagnetic Structures, Including Those Containing Ferrites, Andrea Orlando

Masters Theses

"Application of fast switching amplifiers in power converters, and especially in power inverters, causes unwanted radiated emission, which is a consequence of common mode (CM) currents arising in feed wire bundles. Ferrite chokes are commonly used to suppress those CM currents by increasing the CM impedance of circuits without affecting the differential mode currents, which is important for undisturbed operation of the converters or inverters. Their effective impedance is the main design concern, and it is determined by the material intrinsic properties (permeability, permittivity) and geometry. The goal of this work is to analytically correlate the geometrical and material properties …

Reliability-Based Design With System Reliability And Design Improvement, Gagandeep Singh Saini

Masters Theses

"This thesis focuses on developing a methodology for accurately estimating series system probability of failure. Existing methods for series system based design optimization are not that accurate because they assign reliability to each failure mode; as a result complete system reliability goes down. According to method proposed in this work, the user will assign required system reliability at the start and then optimizer will apportion reliability to every failure mode in order to meet required system reliability level. Detlevson second order upper bounds are used to estimate system probability of failure. Several examples have been shown to verify the results …

Screw Connections Subject To Tension Pull-Out And Shear Forces, Ryan M. Francka

Masters Theses

"Currently, the behavior of screw connections subject to combined tension pull-out and shear forces is not well understood. An experimental study was conducted at Missouri University of Science and Technology to better understand the relationship or interaction between these forces. The test program evaluated four parameters that may influence the behavior of pure tension and pure shear in screw connections: the thickness of the sheet not in contact with the screw head, the ultimate strength of the steel, the ductility of the steel, and the screw diameter. This investigation extends the application of the pure pull-out and pure shear equations …

Fault Detection And Prediction With Application To Rotating Machinery, Gary R. Halligan

Masters Theses

"In this thesis, the detection and prediction of faults in rotating machinery is undertaken and presented in two papers. In the first paper, Principal Component Analysis (PCA), a well known data-driven dimension reduction technique, is applied to data for normal operation and four fault conditions from a one-half horsepower centrifugal water pump. Fault isolation in this scheme is done by observing the location of the data points in the Principal Component domain, and the time to failure (TTF) is calculated by applying statistical regression on the resulting PC scores. The application of the proposed scheme demonstrated that PCA was able …

Formation Of Iron-Rimmed Sandstone Nodules On Earth; Terrestrial Analogue For The Formation Of Martian Blueberries?, Katherine Charlotte Muller

Masters Theses

"NASA's twin Mars Exploration Rovers, MER, Spirit and Opportunity, have identified numerous geologic features that hint at a watery past on Mars noted in Malik, 2004. Prominent among these features are the "Martian Blueberries" that occur as spherical hematite (Fe₂O₃) nodules. Hematite formation is facilitated by the presence of water, although there are presently no known sources of free liquid water on Mars. Chan et al., 2004 states that these "blueberries" are also similar to nodules found in the Jurassic aged Navajo Sandstone in Utah. An understanding of the processes controlling the formation of the Utah nodules may thus be …

Feasibility Of A Human Performance Model In Consequence Management, Kashmeera Ghosh

Masters Theses

"Human civilization has always encountered unpredictable disasters as a result of natural events. Now it also faces the disasters caused by terrorist attacks. Governments must have consequence management plans in place to protect public health and safety, restore essential services, and provide emergency relief to affected businesses and individuals. Human performance models predict outcomes in complex dynamic situations. Such models can simulate disaster management procedures under varying circumstances. This work applies human performance modeling in a terrorist situation and evaluates possible uses of such models by first responders in practical consequence management applications. It includes a case study of an …

Real-Time Reconfiguration Of Programmable Logic Controller Communication Paths, Curtis Alan Parrott

Masters Theses

"This thesis explores the topics related to reconfiguration of Programmable Logic Controller's (PLC's) communications paths as it relates to network security and reliability. These paths are normally fixed, which creates a single fault point which can easily be disrupted by network failure or network based attack. With the ability for autonomous communications path reconfiguration these disruptions in communications can be avoided or bypassed. This work builds on these principles and a series of PLC programs are developed to facilitate several things: Scanning of the three different network types most common in PLC to PLC communications; a comprehensive network scan routine …

Friction Stir Processing Of Magnesium Alloys, Gaurav Bhargava

Masters Theses

"Magnesium alloys have been fast catching up their attention in applications where both lightweight and exceptional strength is desired. But magnesium alloys suffer formability issues which limit their use to cast applications when designing complicated shapes. Friction stir processing (FSP) is technique for, imparting a fine-grained, homogeneous microstructure by which both strength and ductility can be enhanced. The results from the first part of present work showed that AZ31 alloy when employed the use of FSP, yielded significant strength and ductility gains but on the cost of anisotropy. The cause of anisotropy was investigated to be correlated to texture evolution …

Synthesis Of Surface Composites Using Friction Stir Processing, Bharat Gattu

Masters Theses

"Composite materials have an edge over monolithic materials due to higher strength/stiffness - to - density ratios, improved fatigue and wear resistance and better high temperature properties. Surface composites provide improved tribological properties such as wear resistance, friction coefficient and corrosion resistance. Friction stir processing (FSP) which originated from friction stir welding (FSW - a method for joining aluminum alloys) is a solid state technique to modify the microstructure of the alloys. During FSP the frictional heat generated at the tool - work piece interface plasticizes the material allowing it to flow around the pin. The combined effect of the …

Development And Use Of Computer Aided Tools To Enhance Team Dynamics With Role Play Simulations, Vachaspathy Kuntamukkala

Masters Theses

"This thesis proposes a methodology for the development and use of computer based tools to enhance student team dynamics. Working effectively in groups cannot be taught in class room environment. Students often encounter conflicts during team meetings. Although some conflicts are resolved by the efforts of team members, an unbiased facilitator who is not a member of the team is often needed to help. This work proposes a tool that uses role play simulations to engage students in real-life scenarios so that they gain a practical, as well as a theoretical, understanding of how to work effectively as a team. …

In-Plane Behavior Of Strengthened Unreinforced Masonry Infill Walls With Alternative Wood-Fiber Fly Ash Material, Yosuke Tanizawa

Masters Theses

"This research investigates the potential for an alternative masonry product to use in masonry infill wall systems. The study also investigates the effects of an external fiber reinforced polymer (FRP) strengthening system on in-plane behavior of the alternative unreinforced masonry (URM) walls. The alternative masonry product is produced in a solid unit configuration and utilizes recycled white oak wood-fibers and an ASTM Class-C fly ash as its raw materials. The external strengthening system investigated consists of an elastomeric polyurea surface coating with and without integrated discrete chopped E-glass fibers which is directly sprayed on the URM wall surfaces. The alternative …

The Development And Application Of The Complete Time-Domain Trl Calibration Technique, Hongxia Ning

Masters Theses

"The first paper in the thesis discussed the development of a complete time-domain THRU-REFLECT-LINE (t-TRL) calibration technique. To validate the error correction technique, two stripline TRL test fixtures are designed and measured by two TDR instruments respectively. The t-TRL calibration is implemented to the recorded TDR/TDT waveforms and the comparison of the magnitude and phase results of S-parameters obtained by t-TRL and VNA TRL shows excellent agreement up to 25GHz.

In the second paper, the application of t-TRL calibration technique to the Root Impulse Energy (RIE) loss calculation is discussed. The RIE loss is theoretically derived for the matched network …

The Effects Of Water To Fuel Ratio On The Kinetics Of Supercritical Water Reformation Of Jet Fuel, Satya Putta

Masters Theses

"The noncatalytic direct reformation of jet fuel was studied in a supercritical water medium using a specially designed 400-mL Haynes® 230 alloy tubular reactor. The experiments were conducted at 1042±5 K, 240.9±0.1 bar, and at water flow rates of 7.5, 15, 30 g/min with varying water-to-fuel feed ratios of 7.5, 15 and 30. The principal reactions are direct reformation of jet fuel into hydrogen and carbon oxides and pyrolysis of jet fuel into lighter hydrocarbons and coke. The effluent gas contained H₂, CO, CO₂ and CH₄, with smaller concentrations of C₂H₄ and C₂H₆. This thesis discusses the effects of the …

An Evolutionary Algorithm Approach To Actuated Signal Timing Optimization Under Lane-By-Lane Detection Condition, Eric G. Strack

Masters Theses

"Motivated by the need to reduce congestion on the nation's roadway network, this research seeks to determine when a new detection scheme at actuated signalized intersections may help. This new detection scheme is called lane-by-lane detection. It "looks" at traffic in all lanes individually to determine the traffic volume on the roadway. Specifically, the problems addressed are investigating alternate signal timings and investigating the traffic volume's effect on performance of the detection scheme. For the alternate signal timings, an Evolutionary Algorithm (EA) was employed to identify the optimal signal timing. This algorithm creates signal timings and tests them in the …

Spectral And Spatial Analysis Of False Alarms In Airborne Minefield Data, Abhishek Sanaka

Masters Theses

"Tests run in May 2005 at an arid site as part of airborne minefield detection yielded substantial airborne background data with ground truthed and surveyed false alarm locations. ERDC and MultiSensor LLC identified the locations, geo referenced and documented different false alarms. The project reported here built a self-contained database of image chips recording target signatures for MSI (four bands) and MWIR sensors for false alarms from this background data and mines from related areas. The image chips represent various days, times of day, altitudes, as well as several different sources of false alarm and mine types. The database facilitates …

Golan V. Gonzalez And The Changing Balance Between The First Amendment, Copyright Protection, And The Rest Of The World, Carrie Claiborne

Denver Law Review

No abstract provided.

Danger - Bombs May Be Present - Cannon V. Gates: A Jammed Cannon Preempts Citizen Suit Indefinitely, Theresa Sauer

Denver Law Review

No abstract provided.

Project Collaboration In A Distributed Environment, Shriroopa Prabhakar Deshpande

Masters Theses

"This thesis investigates methods of managing projects in an environment where project team members are in different locations. Today, large scale projects undertaken by firms that have a global presence are successfully developed across time, distance, and geographic boundaries. In order to survive in this environment, firms face many project challenges, including diverse employees, various work practices, and communication issues. Many communication issues can be minimized by the proper use of collaborative tools as well as by sharing expertise, coordinating activities, and managing relationships. Web-enabled project management tools have enhanced efforts to increase the quality, competitiveness, and profitability of these …

Emi Chip-To-Tem Cell Coupling For A Microcontroller And Emi Coupling Resulting From Via Transition And Reference Plane Change, Hemant Bishnoi

Masters Theses

"The work presented in this thesis can be broadly categorized under two main headings, estimation of electromagnetic interference (EMI) performance and characterization of EMI performance.

A numerical model of capacitive coupling between two orthogonally crossing double stripline was developed earlier by Kenji Araki and Yoshio Kami at the University of Electro-Communications, Japan. Their model was shown to be accurate up to 3GHz. A verification of their numerical model with full wave simulations is presented here.

In another work done by Shaohua Li, dynamic currents in the power pins of a microcontroller were predicted by using an IC model. The ultimate …

Adapting Management Strategies To Enter New Global Markets, Karuna Vineetha Vemulapalli

Masters Theses

"With globalization spreading its roots into every country, people from various countries are working together, and will be trying to understand the cultural differences between the organizations in different nations. Effective management of the cultural differences will be an important and competitive advantage. Keeping in mind the different perceptions of the term “Management” by varying cultures, namely United States and India, this research will be focused on understanding and managing these differences.

The proposed research will deal with concepts of cultural diversity, economic differences, intercultural and organizational differences between the two countries. Understanding why some factors like motivation, responsibility, and …