Engineering Commons^™

Solid State Fault Interruption Devices In Medium Voltage Distribution Systems With Distributed Generators, Mehul Kiran Madan

Masters Theses

"Faults in electric power grids often result in long term interruption of electricity supply. The frequent and the sudden occurrences of faults undermine the reliability and continuity of electric networks. However, the new age digital economy demands a continuous supply of electricity of high power quality. This demand of continuous supply and the effort to increase the penetration of renewable power sources into the electric grid has led to a need of highly efficient and flexible systems with the ability to provide power of very high quality. The solid state fault interruption device (SSFID) is one amongst those devices. It …

Zinc Iron Phosphate Glasses For Enameling Applications, Sagnik Saha

Masters Theses

"New compositions of low temperature black glasses were developed that are suitable as frits for enameling soda-lime silicate (S-L-S) glass substrates. Zinc iron phosphate glasses are of interest for this application because they possess dilatometric low softening points (under 600ºC) and have coefficients of thermal expansion that are compatible with S-L-S glass (in the range 90-110x10⁻⁷/ºC). The development of compositions with excellent chemical durability, particularly in acidic conditions, is also desired. Compositional modification were made to the (Na₂O+K₂O)·ZnO·MnO·Fe₂O₃·P₂O₅ glass system using design of experiments. The compositional boundaries used in the design were based on earlier work at Missouri S&T. The …

Standoff Raman Spectroscopy Detection Of Trace Explosives, Abhijeet Singh

Masters Theses

"During the 2003-present Iraq war, Improvised Explosive Devices (IEDs) are being used extensively by the terrorists against the coalition forces and these IEDs were responsible for 40% of coalition force casualties, by the end of 2007. As these IEDs are not based on standard production formulae, their tracking and detection becomes extremely complicated. Laser Induced Breakdown Spectroscopy (LIBS) and Raman Spectroscopy are among the many techniques that have shown promise in detection of explosive compounds. However, the performance of these systems is dependent on the concentration of explosives and ambient noise.

The research presented in this thesis applies signal processing …

A Real-Time Visualization Of An/Pss-14 Audio Alert Signals For Land Mine Detection Validation, Nitin Kolekar

Masters Theses

"The central idea of the current research is visualization of audio alerts from AN/PSS-14. A visualization device connected to the arm of PSS-14 will show real-time display of MD and GPR Audio Alert signals from PSS-14. This visualization device displays both amplitude-time and spectral frequency-time formats of the signals. The latter format achieves visual separation of combined, simultaneous, MD and GPR alerts. The joint occurrence of MD and GPR signals in a specific time window confirms the presence of landmine. This window is defined by the time of occurrence of MD peak and time of occurrence GPR diffraction from onset …

Thermodynamic Based Modeling For Nonlinear Control Of Combustion Phasing In Hcci Engines, Joshua Bradley Bettis

Masters Theses

"Low temperature combustion modes, such as Homogeneous Charge Compression Ignition (HCCI), represent a promising means to increase the efficiency and significantly reduce the emissions of internal combustion engines. Implementation and control are difficult, however, due to the lack of an external combustion trigger. This thesis outlines a nonlinear control-oriented model of a single cylinder HCCI engine, which is physically based on a five state thermodynamic cycle. This model is aimed at capturing the behavior of an engine which utilizes fully vaporized gasoline-type fuels, exhaust gas recirculation and intake air heating in order to achieve HCCI operation. The onset of combustion, …

Dynamic Networking For Programmable Logic Controller Communication, Richard Andrew Hardison

Masters Theses

"This thesis confronts the issue of set path communication in Programmable Logic Controllers (PLCs). In order to increase reliability in a networked automated process, it is necessary to develop a dynamic method of communication between PLCs. Three methods for dynamic messaging in PLCs are explored in this work. These methods are based on the real-time reconfiguration of message paths when communication fails on the originally configured path. The simplest method involves replacing the original message block with an Add-On Instruction (AOI) which can accept multiple communication paths and has the ability to switch between these paths to maintain communication. A …

Explosives Recognition And Awareness Training: A Psychological Approach To Pre-Blast Mitigation, James Wade Hawkins

Masters Theses

"The nation's security strategy tends to be reactionary to a specific event. It is rare when established policies have proven successful, even though there is substantial financial and resource investment. The payoff is measured by analyzing the desired minimal effect rather than prevention of the event altogether. Such is the case in combating explosives-related threats. Today, research and development, science and technology, are plugged as the saviors of a post-blast event. Synthetic and composite materials are used to strengthen barriers and cutting-edge technology is utilized to refine the latest in standoff detection. These legitimate measures provide a sense of security …

Graded-Index Fiber Collimator Enhanced Extrinsic Fabry-Perot Interferometer, Yinan Zhang

Masters Theses

"In this thesis, we studied a fringe visibility enhanced extrinsic Fabry-Perot interferometer (EFPI) by fusion splicing a quarter-pitch graded-index fiber (GIF) fiber to the lead-in single-mode fiber (SMF). The performance of the GIF collimator is theoretically analyzed using a ray matrix model and experimentally verified through beam divergence angle measurements. The fringe visibility of the GIF-collimated EFPI is measured as a function of the cavity length and compared with that of a regular SMF-EFPI. At the cavity length of 500µm, the fringe visibility of the GIF-EFPI is 0.8 while that of the SMF-EFPI is only 0.2. The visibility enhanced GIF-EFPI …

The Study Of A Model For Via Transition And The Multi-Layer Via Transition Tool Gui Design, Ketan Shringarpure

Masters Theses

"One of the many challenges faced by engineers working with the present design scenario is to estimate the extent to which a signal, with significant high frequency content, is affected when it is routed on a printed circuit board. The printed circuit board routing will include the transition through the geometries like micro-strip or strip-line transmission lines, via transitions, and irregularities or asymmetries in the aforementioned geometries. One of these discontinuities, the via transition, results in the interaction of the signal on the via and the cavity (plane-pair) through which it passes. The via transition modeling will help characterize a …

Doubly Fed Induction Generator With Integrated Energy Storage System For Smoothening Of Output Power, Nishant Swaraj Chouhan

Masters Theses

"Wind energy is one of the fastest growing renewable energies in the world today. However, integration of wind power into the power system network is still confronting many challenges. One of the main challenges is the suppression of wind power fluctuations. This thesis focuses on integration of wind power with energy storage to overcome the integration challenges. The first part of this thesis investigates the suitability of energy storage systems for transmission, distribution and wind farm applications. A review on the available energy storage systems is performed considering several criteria. Efforts are made to investigate solutions that meet all the …

Modeling The Practical Performance Of Switched-Capacitor Converters And A Method For Automating State-Space Model Generation, Jordan M. Henry

Masters Theses

"A new modeling technique and a method for automating the modeling process are introduced for analyzing complex switched-capacitor (SC) converters. The model uses conventional circuit analysis methods to derive state-space models of each switching state. Steady-state performance is derived and expressed as an equivalent resistance. Whereas previous techniques have provided either the detailed performance of a simple SC converter or the limiting performance of a complex SC converter, this new model is flexible enough to provide detailed performance for any practical converter. Nonuniform component choices, asymmetric duty cycles, and other deviations from an ideal converter can be readily included. Dynamics …

Controlling Strength And Permeability Of Silica Investment Casting Molds, Darryl M. Kline

Masters Theses

"Investment casting is a metal casting process in which a ceramic mold is created around a disposable pattern using dip coating. The fine silica flour making up most of the mold gives the benefits of a smooth internal mold surface and high density. The high density allows for investment casting molds to be thinner and lighter than sand-based molds, but gives substantially smaller gaps between particles for air flow. This research focused on the design and improvement of the formulation for making investment casting molds with customizable physical properties. Properties of the molds, specifically flexural strength, permeability, and physical structure, …

Reverberation Reduction In A Room For Multiple Positions, Raghavendra Ravikumar

Masters Theses

"Reverberation in a room occurs when the direct path sound from a sound source undergoes multiple reflections from the walls of the room before reaching the listener. An impulse response of the room can be measured called the room impulse response (RIR) which captures the effects of the room. This can be represented digitally on a computer. A filter is designed to cancel the effects of the room using the information in the room impulse response. This filter is called an equalization filter and is usually placed between the source signal and loudspeaker to perform the equalization. The RIR changes …

Quantification Of Uncertainty In Aerodynamic Heating Of A Reentry Vehicle Due To Uncertain Wall And Freestream Conditions, Benjamin R. Bettis

Masters Theses

"The primary focus of this study is to demonstrate an efficient approach for uncertainty quantification of surface heat flux to the spherical non-ablating heatshield of a generic reentry vehicle due to epistemic and aleatory uncertainties that may exist in various parameters used in the numerical solution of hypersonic, viscous, laminar blunt-body flows with thermo-chemical non-equilibrium. Two main uncertainty sources were treated in the computational fluid dynamics (CFD) simulations: (1) aleatory uncertainty in the freestream velocity and (2) epistemic uncertainty in the recombination efficiency for a partially catalytic wall boundary condition. The Second-Order Probability utilizing a stochastic response surface obtained with …

Measuring Blast Induced Rock Damage From Pre-Splitting Sandstone By Applying The Multichannel Analysis Of Surface Waves Geophysical Method, Charles Bradford Zdazinsky

Masters Theses

"Many blasting applications in the mining industry demand that the hard rock being blasted remains structurally competent. For example, pre-splitting is a common technique to reduce fracturing, and operators of dimension stone quarries use this blasting method to eliminate overbreak. When pre-split design parameters are not applied correctly, there will be a redistribution of stresses within the rock, resulting in Blast Induced Rock Damage (BID). Advances in geophysical technology are enabling blast technicians to monitor BID and then use the results to correctly design their blasts. The Multichannel Analysis of Surface Waves (MASW) geophysical method is new technology that is …

Enhanced Photorefractivity In A Polymeric Composite Photosensitized With Modified Carbon Nanotubes, Naveen Kumar Lingam

Masters Theses

"This work involves the photosensitization of photorefractive polymeric composites through the inclusion of multiwalled and singlewalled carbon nanotubes grafted to poly(N-vinyl carbazole). The photorefractive nature of the holograms gratings was established using two-beam-coupling, yielding two-beam-coupling gain coefficients approaching 80 cm⁻¹. Degenerate-four-wave-mixing experiments exhibited diffraction efficiencies as high as 60% as well as over-modulation voltages as low as ~ 40 V/µm. These notable figures of merit indicate that the grafting of the various carbon nanotubes to the poly(N-vinyl carbazole) polymer resulted in enhanced photorefractive performance. The mechanism responsible for this enhancement in photorefractive performance is investigated using a variety of experimental …

Methodology And Applications Of Electrostatic Discharge Current Reconstruction By Near-Field Scanning Technique, Wei Huang

Masters Theses

"Electrostatic discharge (ESD) can cause interference in or damage to circuits or systems in many ways e.g., by E- field or H- field coupling or via conduction paths. Although one can roughly estimate the voltage and current at the injection location during an ESD event, the real offending parameter is mostly the ESD current spreading throughout the system. Those currents can be simulated if great simplifications of the system are acceptable. However, even in moderately complex systems, the ability to simulate is limited by a lack of models and computational resources. Independent of the complexity, but obviously not free of …

Automation Of Cad Model Based Assembly Simulations Using Motion Capture, Anup Madhav Vader

Masters Theses

"The manufacturing industry often uses text and video as a supplement for worker training procedures. Unfortunately, text is often difficult to follow and video lends itself to occlusion issues. CAD based animations of assembly operations can overcome these shortcomings while offering greater potential for operations analysis and simulation flexibility. However, creating such CAD based training simulations manually is a time intensive task and many a times fail to reveal the practical assembly issues faced in the real world. Thus, it is highly beneficial to be able to automate these simulations using motion capture from a physical environment. This thesis research …

Development Of Novel Backscatter Communication Systems Using A Multi-Hop Framework And Distributed Beamforming, Vikram Reddy Surendra

Masters Theses

"The goal of this thesis it to develop a wireless networking framework for battery-free devices based on passive, backscatter communication. In contrast to traditional, active communication systems, where the radio signal has to be generated using large amount of energy from batteries, the passive systems reflect the RF signal. The information is encoded by modulating the reflected signal, which consumes significantly less energy than active transmission. The existing passive, backscatter systems have limited communication capabilities. For example, the Radio Frequency Identification (RFID) systems support short-distance, direct communication between active reader and passive tags. The communication range is limited due to …

Design And Critical Performance Evaluation Of Horizontal Axis Hydrokinetic Turbines, Suchi Subhra Mukherji

Masters Theses

"The current work discusses the hydrodynamic performance of horizontal axis hydrokinetic turbines (HAHkT) under different turbine geometries and flow conditions. Hydrokinetic turbines are a class of zero-head hydropower systems which utilize kinetic energy of flowing water to drive a generator. However, such turbines often suffer from low-efficiency. A detailed computational fluid dynamics study was performed using a low-order k-[omega] SST (Shear Stress Transport) turbulence model to examine the effect of each of tip-speed ratio, solidity, angle of attack and number of blades on the performance of small HAHkTs with a power capacity of 10 kW. The numerical models (both two-dimensional …

Neural Mrac Based On Modified State Observer, Yang Yang

Masters Theses

"A new model reference adaptive control design method with guaranteed transient performance using neural networks is proposed in this thesis. With this method, stable tracking of a desired trajectory is realized for nonlinear system with uncertainty, and modified state observer structure is designed to enable desired transient performance with large adaptive gain and at the same time avoid high frequency oscillation. The neural network adaption rule is derived using Lyapunov theory, which guarantees stability of error dynamics and boundedness of neural network weights, and a soft switching sliding mode modification is added in order to adjust tracking error. The proposed …

Slip Ramp Spacing Design For Truck Only Lanes Using Microscopic Simulation, Manoj Vallati

Masters Theses

"This research work proposes recommendations for slip ramp spacing between the TOLs and the general GPLs along Missouri rural interstate highways using a microscopic simulation model, VISSIM. Simulation of peak period rural traffic conditions indicated that heavy vehicle speeds were directly proportional to the lengths of the merge, diverge, and link sections. The proposed design recommendations for slip ramp spacing are based on the results of these section lengths. Design of experiments was carried out using a central composite design. As the slip ramp spacing depended heavily on the lane change behavior of drivers, a sensitivity analysis was performed of …

A Value Model For Product Development Process Using Lean Principles, Salik Yadav

Masters Theses

"This research presents a value quantification model for multi-stage product development Process (PDP) using lean value principles. The PDP stages considered in this research include conceptual development, systems design, detailed design and prototyping stages. The value at any of the PDP stages is formulated as a function of six factors: (a) importance of customer requirements, (b) cost of customer's ownership, (c) parts/service availability, (d) weighted average cost of capital, (e) information evolution, and (f) risk reduction. Factors (a)-(d) are adequately addressed in the literature. This study focuses on information evolution and risk reduction factors. These two factors are defined by …

An Analysis Of The Integration Of Lean And Safety, Pankaj Mahesh Pai

Masters Theses

"The lean philosophy has proven potential to help businesses improve productivity and reduce its losses. Lean can give businesses a cutting edge in this age of global competition. The fundamental principle of lean is to identify wastes in the system and reduce or eliminate them. There is a concern that during lean implementations, the focus on productivity may result in health and safety issues being ignored or worse, changes driven by lean may introduce new hazards. The relationship between lean and safety is not clearly understood. Lean and safety should be compatible. Both strive to improve processes. Both are against …

Strategic Process Integration Of Energy And Environmental Systems In Wastewater Treatment Plants, Bharath Kumar Gangichetty

Masters Theses

"Green environmental practices are increasingly important in combating serious global energy and environmental issues. Most wastewater treatment facilities were built when energy costs were not a concern; however, an increasing demand for energy, changing climatic conditions, and constrained energy supplies have resulted in the need to apply more energy-conscious choices in the maintenance or upgrade of existing wastewater treatment facilities. A detailed analysis of the majority of water and wastewater treatment services shows that most facilities operate far below the efficiency levels needed for effective energy use. Failure to comply with regulated environmental standards is also a problem. Although standards …

A Comparison Of Case-Based Reasoning And Regression Analysis Approaches For Cost Uncertainty Modeling, Karan Banga

Masters Theses

"This thesis presents case-based reasoning approach for estimating the cost and modeling cost uncertainty of a new product in the concept selection stage. Case-based reasoning (CBR) is an approach which uses old cases/experiences to understand and solve new problems. The CBR approach consists of creating a knowledge-base (or database) containing past cases (products), defining a new case (concept), retrieving cases similar to the new case, and adjusting the solution of the retrieved cases to the new case. The first paper compares case-based reasoning, in studying the effects of varying design attribute specifications on cost estimation accuracy and cost distribution reliability. …

Strategic Criteria For Evaluating Inland Freight Hub Locations, Robert Tyler Lipscomb

Masters Theses

"The aim of this thesis is to develop criteria that can be used to evaluate the current capabilities and sustainability of inland freight hubs. A review of the literature highlights the need for a more efficient freight distribution system to combat supply chain deficiencies and the important role that inland freight hubs play in creating this system. Also in the literature is a call for a more comprehensive approach to hub development decisions and the use of multi-criteria decision analysis. The decision to devote resources to logistics developments in a specific region must consider many factors that are both quantitative …

Prediction Of Soft Error Response Of Integrated Circuits To Electrostatic Discharge Injection Via Simulation Field; Package Interaction For Electrostatic Discharge Soft Error Prediction; Full Wave Model For Simulating Noise Ken Electrostatic Discharge Generator, Argha Nandy

Masters Theses

"In the first section, a concept for analyzing soft error response in ICs to ESD via coupling through flex cable structures is presented. Its novelty lies in accounting for the transient electromagnetic fields radiated by the ESD generator that couples to the flex cable PCB thereby causing disturbance on the IC under test. This is accomplished in three stages; first by developing a full wave model of the DUT which includes modeling the PCB and flex cable geometry and validating it in frequency domain with regard to the transfer impedance. This followed by combining the ESD generator with the DUT …

The Effects Of Personal Protective Equipment Level A Suits On Human Task Performance, Yvette L. Simon

Masters Theses

"First response teams dealing with hazardous substances often require the highest level of protection provided by Level A suits. These suits are fully encapsulating, bulky, and heat retentive. The effect of these suits on the wearer's ability to perform various tasks is of interest when it comes to human performance analysis. This research effort examined the effect of the Level A suit on fine motor and gross motor dexterity. Seven members of the National Guard's Civil Support Team (CST) performed a battery of six tasks designed to test these abilities. Tasks comprised the Minnesota Dexterity test and the Mirror Tracer …

Design And Development Of Microwire Feeder For Laser Applications, Amogh J. Shenoy

Masters Theses

"This thesis focuses on the design and development of a microwire feeder for laser applications. The use of wire-feeders in laser welding and electrical discharge machining applications has been prominent which can handle wire of 0.25 mm and it can go up to 10.0 mm in other applications. Development of microwire handling devices is complicated and difficult due to its low buckling strength; the need for high accuracy for its use; and the harsh environment it is exposed to, in laser applications. This paper presents a systematic methodology for the design and development of a high-precision microwire handling device. This …