Engineering Commons^™

Evaluation Of Skin-Core Adhesion Bond And Low-Velocity Impact Behavior Of Honeycomb Sandwich Structures, Ramanjaneya R. Butukuri

Masters Theses

"Composite sandwich structures offer several advantages over conventional structural materials such as lightweight, high bending and torsional stiffness, superior thermal insulation and excellent acoustic damping. Some of the failure mechanisms in a composite sandwich structure are de-bonding of the composite facesheets from the core structure and damage due to low-velocity impact. In the first part of this work, adhesive fillet formation and adhesive mechanical strength are evaluated as a function of several different sandwich construction design variables. The effect of film adhesive thickness is studied. A process for reticulation of the adhesive is applied and studied. Optimized combinations of core …

Development Of Lower Cost Imaging Systems For Laser Metal Deposition Process, Shyam Barua

Masters Theses

"Laser Metal Deposition (LMD) has been used as an additive manufacturing process in industries such as aerospace and die castings. LMD is especially useful in repair applications involving die repair. However, it is still not used widely in industry due to variations in the quality of parts. There are multiple interactions between various factors which influence the quality of deposit.

There exists a need for defect detection systems to detect any changes in the deposition quality during deposition. On demand detection enables adjustment in process parameters and minimization of rework cost.

Vision systems have been used extensively in the industry …

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 …

"Long" Carbon Fiber Reinforced Concrete For Impact And Blast Resistance, Benjamin Paul Gliha

Masters Theses

"One of the most commonly used materials for protective structures and construction is traditional reinforced concrete. However, in a blast, conventional reinforced concrete (RC) is susceptible to significant spalling (small to medium size chunks of concrete detaching from the original member). The force of the blast turns spalled concrete into projectiles, resulting in secondary fragmentation and the majority of loss of life. Furthermore, the concrete debris makes for difficult and uncertain footing. Both phenomena endanger personnel and complicate post-blast recovery efforts. A very promising but barely explored change to conventional RC construction is the addition of "long" carbon fibers (fibers …

Intelligent Control Of Smartparks And Wind Farms In Smart Grids, Priyam Chakravarty

Masters Theses

"With development in wind turbine technology, wind energy has become an important contestant in the utility market. However, wind energy has the intrinsic property of variations which causes fluctuations in the power grid.

Plug-in electric vehicles are drawing the attention of researchers and the electric power industry because of its need for charging from the grid and its ability to store energy. With increase in the numbers of plug-in electric vehicles, there will be significant penetration of distributed energy resources and hence plug-in electric vehicles connected to the grid in parking lots (SmartParks) can be used as energy storage sink …

Life Expectancy Evaluation And Replacement Schedule Development For Led Traffic Indicators, Casey Robert Noll

Masters Theses

"LED (light-emitting diode) technology is being widely adopted for use in sustainable traffic signal management. However, the useful life and luminosity characteristics have not been sufficiently studied in the field to provide departments of transportation with cost-effective replacement strategies based on the realities for LED indicators. LED indicators fail when their luminous intensity (LI) falls below a pre-specified threshold, posing a danger to traffic. This research details a field study of LED indicators in Missouri and develops a replacement schedule based on key findings. Rates of degradation and subsequently the useful life of each type of LED indicator were calculated …

Pressed Powdered Titanium And Aluminum Conical Shaped Charge Penetration Of Geological Targets, Dominique John Nolan

Masters Theses

"Conical Shaped Charge penetration into rock is dependent on the physical characteristics of the rock itself and the design and composition of the shaped charge conducting the work. This study looks at the effects of a non-typical conical shaped charge and its penetration into four different rock targets. The shaped charge is made of a liner, which is not a typical solid but instead is a pressed powdered metallic compound of Titanium (Ti) and Aluminum (AI).

The study presents the raw data from testing against rock targets that range in density, uniaxial compressive strength (UCS), tensile strength, hardness scales, and …

Quantitative Oxygen Imaging With A Display Screen And A Color Camera, Sanghan Park

Masters Theses

"Optical oxygen sensing uses luminophores such as metal complex dyes that respond to oxygen when illuminated by their specific excitation wavelengths. Traditional optical instruments are mostly spectrometric instruments based on the measurements of emission, absorption or reflection. There is, however, a great need to develop simple, economical, photometric detection components toward quantitative and two-dimensional imaging instruments.

In this work, familiar optoelectronic devices were utilized to demonstrate a simple determination method of gaseous oxygen both quantitatively and qualitatively. A liquid crystal display (LCD) screen and a color charge-coupled device (CCD) camera were employed as a light source for fluorescence excitation and …

Design, Analysis, And Optimization Of Composite Structures For Aerospace Applications, Tyler Jason Keil

Masters Theses

"This thesis contains three papers that focus on composites that pertain to a variety of structures commonly found in the aerospace industry. The first paper presents an investigation of the stowage and deployment strength of a thin carbon fiber-reinforced polymer shell capable of being rolled and stowed in a tight rolled configuration. The intent of this structure is for use as a segment of a larger deployable reflective aperture. This study involved finite element analysis of several laminates, coupon-level and full-scale prototype testing, which provided a much needed insight and benchmark of composite shells used in this manner.

The second …

Innovative Air Breathing Design And Output Control For Portable Proton Exchange Membrane Fuel Cell, Amar Bala Sridhar

Masters Theses

"Proton Exchange Membrane (PEM) Fuel Cell Technology is an energy source that can provide several times more energy per unit volume than current lithium ion batteries that are available in the market today. The barriers that exist that prevent the fuel cell from entering the world of portable applications are mainly system architecture integration. The idea is to have a fully functioning fuel cell with optimum power output using an innovative chimney design. Tests were conducted to quantify the advantage of using a chimney with the fuel cell. Further research was done to shed light on how different chimney designs …

A Statewide Analysis Of Highway Safety In Arkansas, Uday R. R. Manepalli

Masters Theses

"This research concentrated on two major aspects of highway safety analysis, hotspot identification and identification of crash contributing factors on highways. The objective of the first part of this thesis is to evaluate two crash frequency, three crash severity and two composite hotspot ranking methods. Based on the limitations of the existing hotspot identification methods (HSID), crash factor method (CFM), a crash severity based HSID method is proposed. A composite rank method (F 1) based on principal component analysis is also proposed. These methods are evaluated using three tests, the site consistency test, the method consistency test, and the total …

A Hybrid Problem-Based And Just-In-Time Inductive Teaching Method For Failure Analysis Instruction, Ryan Michael Arlitt

Masters Theses

"When engineers retire, they take their expert knowledge with them. Preservation of this expert knowledge in a usable form is beneficial for the advancement of any engineering field. Risk in Early Design (RED) is one method for preserving expert risk analysis knowledge. The first purpose of this paper is to examine the usability of RED when incorporated with a hybrid problem-based and just-in-time inductive teaching method for failure analysis instruction. The second purpose of this paper is to propose and perform steps toward verification and validation of the RED methodology and implementation. Evaluation metrics were developed, and several of these …

Full Wave Simulation Of An Electrostatic Discharge Generator Discharging In Air Discharge Mode Into A Product And Quantify Channel Performance Utilizing Novel Time Domain Convolution Method, Dazhao Liu

Masters Theses

"In the first section, it introduces a methodology to simulate the currents and fields during an air discharge ESD into a product by combining a linear description of the behavior of the DUT with a non-linear arc resistance equation. The most commonly used test standard IEC 61000-4-2 requires using contact mode discharges to metallic surfaces and air discharge mode to non-conducting surfaces. In contact mode, an Electrostatic Discharge (ESD) generator is a linear system. In air discharge mode, a highly non-linear arc is part of the current loop. This paper proposes a method that combines the linear ESD generator full …

Optimal Integrator-Less Tracking Controller For Uncertain Systems, Anusha Mannava

Masters Theses

"Tracking controllers are designed to drive the system on the desired trajectory with minimum error. In real life, all systems have uncertainties such as friction, modeling inaccuracies or damage that cause the performance to deviate from the ideal response. This research is aimed at addressing the tracking problem in the optimal context and a generalized method to handle the uncertainties is proposed. In the first paper, an optimal tracking controller without an integral component is formulated for a linear system. This design can handle time varying, non-zero references and effectively alleviates the risk of 'wind up'. A neural network based …

Residential Energy Monitoring: Missouri S&T Solar Village Development, Christopher David Wright

Masters Theses

"As energy costs are rising, public and private sector groups are searching for improved energy efficiency technology. Research tools for predicting residential energy usage are lagging behind commercial developments. Missouri S&T has a unique and strong opportunity to strengthen its involvement in the development of residential energy research and knowledge. The S&T Solar Village, a collection of homes designed for energy efficiency and renewable energy, is poised to support this research. This thesis develops a design for residential energy evaluation and data collection of the four solar homes in the Village. The energy evaluation system identifies over 300 sensors and …

Detection And Estimation Of Image Blur, Harish Narayanan Ramakrishnan

Masters Theses

"The airborne imagery consisting of infrared (IR) and multispectral (MSI) images collected in 2009 under airborne mine and minefield detection program by Night Vision and Electronic Sensors Directorate (NVESD) was found to be severely blurred due to relative motion between the camera and the object and some of them with defocus blurs due to various reasons. Automated detection of blur due to motion and defocus blurs and the estimation of blur like point spread function for severely degraded images is an important task for processing and detection in such airborne imagery. Although several full reference and reduced reference methods are …

Power Distribution Network Inductance Calculation, Transient Current Measurement And Conductor Surface Roughness Extraction, Fan Zhou

Masters Theses

"The first part in the thesis discussed the modeling of the mid-frequency inductance for Zpp type plane pairs in power distribution networks (PDN). It is a key step for the placement of the decoupling capacitors. This paper gives an efficient approach for the calculation of the inductance for different capacitor placements. The PEEC based formulations takes advantage of the opposite currents in the planes. This leads to compute time reductions and memory savings for both the element calculation and the matrix solve step. A formulation is used where placement of capacitors leads to only small changes in the circuit matrix. …

Microalgae Harvesting By Flocculation With Polymer-Coated Magnetite Particles, Humayun Shariff

Masters Theses

"Although microalgae are considered to be one of the potentially significant feedstock for renewable biofuels, harvesting them efficiently from culture ponds has been a major hurdle. The conventional harvesting methods such as centrifugation and filtration are very time and labor intensive processes. Gravimetrical settlement with the aid of cationic flocculants is the most widely employed technique, but suffers from the difficulty in recovering microalgae floes. Furthermore, recycling of these flocculants after the harvesting process is not possible. Polymer-coated magnetite particles have been investigated for applications in various fields. This research has focused on the development of a novel and efficient …

Experimental Study On Thermal Treatment Of Used Printed Wiring Boards (Pwbs), Xiangjun Zuo

Masters Theses

The availability of cheaper and better electronic products as a result of the rapid innovation in technology in past decades has driven the production of e-waste forward. Printed wiring board (PWB) is a component made of one or more layers of insulating material with electrical conductors. The existing processes of recycling PWBs use pyrometallurgical or hydrometallurgical methods, which generate atmospheric pollution. Green recycling has obvious benefits to decrease the amount of PWBs. Green recycling includes two features, 1) little or zero pollution of toxic gases and heavy metals, and 2) efficient (quick and economical) recycling.

The aim of this work …

Maskless Additive Manufacturing Of Micro Structures By Laser Sintering Of Nanoparticles, Vivekram Ramanathan

Masters Theses

"The focus of this study was to investigate an alternate microfabrication process of sintering nanoparticles using a patterned laser light to generate two dimensional (2D) and three dimensional (3D) geometries. With trends of producing electronic and medical devices using cheaper and faster technologies, a new procedure was developed to deposit and bond miniature patterns of silver nanoparticles onto silicon substrates.

The process consists of spraying silver nanoparticles onto the substrate while a patterned or modulated laser beam is focused onto the sprayed nanoparticles. These nanoparticles exposed under the modulated laser light undergo partial melting or sintering and adhere to the …

Decentralized Coordinated Ilc System Design And Transient Growth Control Using Iteration-Varying Filter, Qing Liu

Masters Theses

"In automation control area, with the increasing demand in task complexity and high control precision, coordination between systems is required. There are mainly two types of coordinated systems, decentralized and centralized. This thesis is focused on a large array of coordinated systems, and the decentralized structure is preferred. To achieve high control precision in a coordinated system, many existing approaches may work, and in the system performing the repeating process, Iterative Learning Control (ILC) is a useful approach. Therefore, in this thesis, a decentralized coordinated ILC system is proposed and analyzed. The proposed control system is especially useful in coordinating …

Detection Of Explosive Threats By Using Embedded Wireless Sensor Based Networks, Jake Daniel Hertenstein

Masters Theses

"This thesis focuses on the development of novel schemes for the detection of unintended electromagnetic emissions (UEE) from passive radio frequency (RF) receivers and chemical and biological (CB) agents for the purpose of locating explosive threats (ET) to improve survivability for equipment and personnel in the surrounding environment. The methods and architectures used in this work were developed for use with wireless sensor networks (WSNs). While previous work has shown that highly sensitive equipment is capable of long-range detection of UEE the intention of this work is to develop a network of small, low cost smart sensor nodes (SSNs) capable …

Efficient Modular Arithmetic Units For Low Power Cryptographic Applications, Rajashekhar Reddy Modugu

Masters Theses

"The demand for high security in energy constrained devices such as mobiles and PDAs is growing rapidly. This leads to the need for efficient design of cryptographic algorithms which offer data integrity, authentication, non-repudiation and confidentiality of the encrypted data and communication channels. The public key cryptography is an ideal choice for data integrity, authentication and non-repudiation whereas the private key cryptography ensures the confidentiality of the data transmitted. The latter has an extremely high encryption speed but it has certain limitations which make it unsuitable for use in certain applications. Numerous public key cryptographic algorithms are available in the …

Integration And Characterization Of An Electrical Storage System For A Hydrogen Fuel Cell Plug-In Hybrid Electric Vehicle, Edward Alexei Anculle Arauco

Masters Theses

"Hydrogen fuel cell hybrid vehicles are an advance technology that promises to solve the energy crisis in transportation and green houses emissions. Even more, Plug-in or extended range vehicles can add diversity in energy sources. Extended range vehicles have the capability to extract energy from the grid and hence reduce the cost of operation of the vehicle. EcoCAR: the NeXt Challenge is a Noth [sic] American competition with seventeen schools participating across North America. Missouri S&T is developing a Fuel Cell Plug-in Hybrid electric vehicle which has a large lithium-ion battery able to store 16 kWh. The fuel cell powertrain …

Synergy Between Biology And Systems Resilience, Ashik Chandra

Masters Theses

"Resilient systems have the ability to endure and successfully recover from disturbances by identifying problems and mobilizing the available resources to cope with the disturbance. Resiliency lets a system recover from disruptions, variations, and a degradation of expected working conditions. Biological systems are resilient. Immune systems are highly adaptive and scalable, with the ability to cope with multiple data sources, fuse information together, makes decisions, have multiple interacting agents, operate in a distributed manner over a multiple scales, and have a memory structure to facilitate learning. Ecosystems are resilient since they have the capacity to absorb disturbance and are able …

Analysis Of The Theta-D Filter As Applied To Hit-To-Kill Interceptors And Satellite Orbit Determination, Michael W. Dancer

Masters Theses

"When designing feedback control systems, there is often a need for estimation methods that provide system information that is not readily available via sensors placed within the system. In many cases a sensor that measures a particular system state either does not exist or is prohibitively expensive. In addition, all realistic systems contain some degree of nonlinearity. This thesis focuses on two such cases: missile guidance with bearings-only measurements and GPS satellite orbit determination. In each case, a new nonlinear filter, the [theta]-D method, is used and evaluated for its performance in providing the necessary estimation. To aid the filter …

Internet-Accessible Hot Cell With Gamma Spectroscopy At The Missouri University Of Science And Technology Research Nuclear Reactor, Edwin Grant

Masters Theses

A dual-chambered internet-accessible heavily shielded facility with pneumatic access to the University of Missouri Science and Technology (Missouri S&T) 200 kW Research Nuclear Reactor (MSTR) core has been built and is currently under low level irradiation testing. The facility allows distance users doing collaborative work with Missouri S&T researchers to manipulate and analyze neutron irradiated samples remotely. The system consists of two shielded compartments, one for multiple sample storage (up to 11 samples), and the other for isolated radiation measurements and spectroscopy. The second chamber has multiple detector ports, graded shielding, and has the capability to support gamma spectroscopy using …

Energy-Efficient Task-Scheduling And Networking Protocols For Secure Wireless Networks, Sandeep Kolli

Masters Theses

"The performance of wireless networks is dependent on a number of factors including the available energy, energy-efficiency, data processing delay, transmission delay, routing decisions, security overhead, etc. Traditionally, due to limited resources, nodes were tasked with only collecting measurements and sending them to a base station or central unit for processing. With increased capabilities of microprocessors the data processing is pushed more toward network and its more capable nodes. This thesis focuses to virtualize the processing resources of the entire network and dynamically distribute processing steps along the routing path while optimizing performance. Additionally, a new multi-key encryption (MKE) scheme …

The Properties And Structure Of Tin Phosphate Glasses Modified With Other Oxides, Jong Wook (Austin) Lim

Masters Theses

"The main objective of this research was to evaluate the properties and structures of glasses from the stannous (SnO) phosphate system for possible use in low temperature optical applications. Glasses in the binary xSnO-(100-x)P₂O₅ system (50 ≤ x ≤ 70) were prepared and their thermal and optical properties were evaluated. Differences in glass transition temperatures (T_g) measured here and reported in the literature were explained by differences in the residual water content in the glasses, as determined by infrared spectroscopy. In general, increasing the SnO content of the binary glasses increased the refractive index and the glass transition …

Validation Of Driving Simulator And Driver Perception Of Vehicle Mounted Attenuator Markings In Work Zones, Durga Raj Mathur

Masters Theses

"This research work sought to validate the driving simulator at Missouri University of Science and Technology and to evaluate the vehicle mounted attenuator (VMA) markings for various times of day. For comprehensive validation of the driving simulator, a framework is proposed which is demonstrated using a fixed-base driving simulator. Objective and subjective evaluations were conducted, and validation of the driving simulator was performed at specific locations and along the highway. Field data were collected for a partial lane closure using a global positioning system (GPS) along the work zone and supplemented with video recordings of traffic data at specific locations …