Engineering Commons^™

Performance Evaluation Of Existing Analytical Methods To Compute The Shear Contribution Provided By Externally Bonded Frp Sheets In Concrete Structures, Rocio Patricia Tumialan

Masters Theses

"External application of FRP composites has been adopted for strengthening and/or repair of concrete structures in many applications during the last two decades. However, the research into shear strengthening using FRP composites has not been widely conducted as compared to flexural strengthening and axial load capacity increase, and the results obtained thus far are scarce and sometimes controversial. This study presents a review of analytical studies and design guidelines on shear strengthening of concrete structures with externally-bonded FRP laminates, and their assessment with experimental data collected from the literature. The strengths and weaknesses of each model and design guidelines/codes/specifications are …

Energy-Aware And Secure Routing With Trust Levels For Wireless Ad Hoc And Sensor Networks, Eyad Taqieddin

Doctoral Dissertations

"This dissertation focuses on the development of routing algorithms for secure and trusted routing in wireless ad hoc and sensor network. The first paper presents the Trust Level Routing (TLR) protocol, an extension of the optimized energy-delay routing (OEDR) protocol, focusing on the integrity, reliability and survivability of the wireless network...The second paper analyzes both OLSR and TLR in terms of survivability and reliability to emphasize the improved performance of the network in terms of lifetime and proper delivery of data...The third paper proposes a statistical reputation model that uses the watchdog mechanism to observe the cooperation of the neighboring …

Field And Laboratory Investigation Of Ozone-Indoor Surface Reactions: Secondary Emissions Inventory And Implications For Indoor Air Quality, Hong Wang

Doctoral Dissertations

"Interfacial chemistry greatly influences human exposure to reactants and products in indoor environments. Emissions of volatile organic compounds, as a result of ozone-surface interactions, can lower an occupant's exposure to ozone, but increase indoor concentrations of odorous and carcinogenic compounds. Therefore, investigation of ozone-surface interactions are necessary for better understanding and controlling exposure to ozone and the products of indoor surface chemistry. In this dissertation, field experiments were conducted in five homes in three seasons to quantify ozone-initiated secondary emission rates (SERs), yields surface reaction probabilities and study their temporal trends"--Abstract, page iv.

Manufacturing And Characterization Of Soy-Based Pultruded Polyurethane Composites, Rama Bhadra Raju Vuppalapati

Masters Theses

"In the recent past, composites have been finding various applications in civil infrastructure, marine, transportation, automotive and non-automotive applications by replacing metals in structural components. Pultrusion is considered to be a cost effective method for manufacturing composite materials.

Polyurethane resin systems form a good alternative to the conventional styrene based systems in pultrusion due to their better physical, chemical and mechanical properties. Polyols derived from soybean oil along with isocyanates produce polyurethanes that can match in many aspects with one derived from the petrochemical polyols. Even though, polyurethanes have good properties there are lots of challenges like designing unique material …

Interactive And Dialogue Based Learning In Engineering Education, Siddartha Thummuri

Masters Theses

"This thesis focuses on a class room architecture that provides high levels of interactivity which enhances the students' learning environment both in distance and on-campus contexts and forms a basis for practical learning. Two analyses are presented in this thesis, the first one being a simple measure of levels of interactivity in this course architecture, based on rubric and the second one, a comparative analysis, to demonstrate the effectiveness of interactive (multi-directional information flow) classrooms as opposed to conventional (unidirectional information flow) classrooms and that this course architecture is ideal for enhancement of distance learning and an excellent route to …

On-Line Inspection And Thermal Properties Comparison For Laser Deposition Process, Yu Yang

Masters Theses

"This thesis is focused on comparing the laser deposition cladding with intended design model and comparing the effect of laser deposition process on thermal properties with traditional welding process. It is research on two aspects of laser deposition cladding. The first part of the thesis is aimed at solving the geometric inspection of laser deposition cladding, and the second part is for comparing the thermal properties of laser deposition cladding to samples of conventional welding process"--Introduction, page 1.

Magnetohydrodynamic Power Generation In A Scramjet Using A Post Combustor Generator, Nathan Lee Mundis

Masters Theses

"A scramjet with a post combustor MHD generator is examined. A quasi-one-dimensional model is developed to calculate the flow path from tip to tail. The model includes losses due to combustion irreversibility, incomplete combustion, chemically reacting flow, friction, MHD losses, and nozzle plume modeling. Flight Mach number, magnetic field strength, gas conductivity, MHD load factor, and MHD generator expansion angle are all varied in order to assess their effects on MHD power generated and thrust lost in the engine. The trends produced through the above variations are summarized in a set of model-fit equations. It is concluded that a post …

Static Evaluation Of The Out-Of-Plane Behavior Of Urm Infill Walls Utilizing Modern Blast Retrofit Systems, Trevor D. Hrynyk

Masters Theses

"Previous investigations have shown that the use of modern retrofit systems can significantly improve the behavior of URM infill walls subjected to variable out-of-plane loads. It has also been shown that the use of externally bonded retrofit systems can greatly reduce the amount of fragmentation and debris scatter that is found to occur in URM walls subjected to high intensity blast loads...The main objective of this study is to investigate, through static testing, the use of modern materials for the purpose of improving the behavior of URM walls subjected to blast loads. This study implemented externally bonded FRP grids and …

The Influence Of Printed Circuit Board Design On Tem Cell Measurements, Vijay Kasturi

Masters Theses

"The IEC 61967-2 integrated circuit radiated emissions test standard describes the use of the TEM cell to measure near-field emissions from an IC. This test requires a printed circuit board (PCB) to mount to IC. The IEC guidelines allow for flexibility in the design of this test PCB which may cause variations in the measured emissions. This thesis studies the impact of typical variations in the PCB design on the measured emissions"--Abstract, page iii.

The Development Of Hybrid Intelligent Systems For Technical Analysis Based Equivolume Charting, Thira Chavarnakul

Doctoral Dissertations

"This dissertation proposes the development of a hybrid intelligent system applied to technical analysis based equivolume charting for stock trading. A Neuro-Fuzzy based Genetic Algorithms (NF-GA) system of the Volume Adjusted Moving Average (VAMA) membership functions is introduced to evaluate the effectiveness of using a hybrid intelligent system that integrates neural networks, fuzzy logic, and genetic algorithms techniques for increasing the efficiency of technical analysis based equivolume charting for trading stocks"--Introduction, page 1.

Analysis Of The Holistic Impact Of The Hydrogen Economy On The Coal Industry, Shannon Perry Lusk

Doctoral Dissertations

"As gas prices soar and energy demand continues to grow amidst increasingly stringent environmental regulations and an assortment of global pressures, implementing alternative energy sources while considering their linked economic, environmental and societal impacts becomes a more pressing matter. The Hydrogen Economy has been proposed as an answer to meeting the increasing energy demand for electric power generation and transportation in an environmentally benign way. Based on current hydrogen technology development, the most practical feedstock to fuel the Hydrogen Economy may prove to be coal via hydrogen production at FutureGen plants. The planned growth of the currently conceived Hydrogen Economy …

Simple And Efficient Solutions To The Problems Associated With Acoustic Echo Cancellation, Asif Iqbal Mohammad

Doctoral Dissertations

"This dissertation is a collection of papers that addresses several important problems associated with acoustic/line echo cancellation (AEC/LEC), specifically double-talk and echo-path change detection. A double-talk detector is used to freeze AEC filter's adaptation during periods of near-end speech. This dissertation presents three different novel double-talk detection schemes. Simulations demonstrate the efficiency of the proposed algorithms"--Abstract, page iii.

Advanced Controller Design Using Neural Networks For Nonlinear Dynamic Systems With Application To Micro/Nano Robotics, Qinmin Yang

Doctoral Dissertations

"The dissertation focuses on neural network (NN) control designs for nonlinear systems with application to micro/nano robotic. Critical problems in nano scale including thermal drift are also addressed"--Abstract, page iv.

The Development And Application Of A Systematic Approach To Evaluating An Academic Department's Brand Meaning, Cassandra C. Elrod

Doctoral Dissertations

"Research of existing literature indicates that below the university level, there has been little effort made in branding academia, namely academic departments. The lack of branding may significantly affect the perceptions that potential students and future employers of these students have about one of these academic units. The impact may be most significant for units where the fields of study that are represented by the department may be unclear, such as in the case of engineering management. However, even in the cases of better-understood fields of study, for example, electrical engineering, the competition for students with other fields of study …

Mechanical Integrity And Behavior Of Thin Films And Their Applications In Mems, Gang Duan

Doctoral Dissertations

"Electric actuated thin films are widely used in micro-electromechanical systems (MEMS) such as radio frequency switches (RF-switches), micro-pumps and valves, and electrostatic actuators. This dissertation will focus on the operation of a MEMS-RF-switch. In a typical MEMS-RF-switch, a mechanically suspended 1-D rectangular or 2-D axisymmetric thin film is pulled by an electrostatic voltage (V₀) applied to an electrode-pad directly underneath. When V₀ exceeds a certain "pull-in" threshold, V₀*, the thin film makes direct contact with the pad so that either an "on" or "off" signal is induced, and when the voltage is removed, the thin film resumes its original undeformed …

Modular Architecting For Effects Based Operations, Emel Meteoglu

Masters Theses

"Effects Based Operations (EBO) is a way of thinking for planning, executing and assessing any operations for the effects they produce, rather than dealing with actions, targets or even objectives. The literature on EBO has been growing day by day; however, there is still a need for modeling techniques and tools that provide more efficient and effective effects based assessment, planning and analysis in order to further develop the capabilities of the operations. In this context, this thesis presents an introduction to EBO by focusing on its methodology, its challenges and also its applicability in different systems. Moreover, this thesis …

E-Design Tools For Friction Stir Welding: Cost Estimation Tool, Pradeep Kumar Tipaji

Masters Theses

"A cost model is an important tool for product design and material selection. An efficient and effective cost estimation tool is necessary for early design evaluation. In this paper, cost estimation models that estimate the production cost for Metal Inert Gas (MIG), Friction Stir (FS), and Friction Stir Spot (FSS) welded joints are presented. These models determine the cost incurred to fabricate each joint along with a detailed explanation of each cost component. Each cost component has been closely analyzed and major cost components have been included in the cost model"--Abstract, page iv.

Friction Stir Processing Of Cast Magnesium Alloys, Timothy A. Freeney

Masters Theses

"This thesis investigates the feasibility and benefits of using friction stir processing as a thermo-mechanical microstructural modification tool for local property enhancement or casting repair of magnesium alloys, specifically high strength EV31A and WE43"--Abstract, page iv.

Bio Inspired Techniques For Simultaneous Design Of Multiple Optimal Power System Stabilizers, Tridib Kumar Das

Masters Theses

"Bio-inspired techniques are fields of study that are inspired from topics of connectionism, social behavior and emergence. Researchers have ventured into the intricacies involved with the techniques and devised algorithms based on their study. Such techniques are the focus of this thesis. The two bio-inspired techniques used for simultaneous design of power system stabilizers (PSSs) in this study are - Particle Swam Optimization (PSO) and Bacteria Foraging Algorithm (BFA). The work in this thesis is presented in three papers as follows: Paper 1 -This paper introduces an improved PSO called Small Population based PSO (SPPSO) with less number of particles …

Vapor Phase Uptake Of Volatile Organic Contaminants By Hybrid Poplar Trees, Sally Rebecca Breite

Masters Theses

"Phytoremediation, the use of plants to immobilize, degrade or remove contaminants from the environment, shows great promise as a remediation technique for many contaminated sites. Phytovolatilization in particular is of great interest for sites contaminated with chlorinated solvents and other volatile organic compounds (VOCs), many of which are recalcitrant to biodegradation. Hybrid poplar trees have been shown to uptake, translocate and volatilize numerous aqueous-phase VOCs, however vapor phase uptake of such compounds has only recently been observed and for only one contaminant, tetrachloroethylene (PCE). One semi-volatile and five volatile compounds were dosed to poplar trees in aqueous and vapor phase …

Performance Improvements Of Automobile Communication Protocols In Electromagnetic Interference Environments, Fei Ren

Masters Theses

"Electromagnetic Interference (EMI) is frequently encountered in automobile communication systems due to a large number of inductive nodes used in these systems. This thesis investigates the effects of EMI on two types of automobile communication systems, the Controller Area Network (CAN) and the FlexRay. It also proposes a modified Automatic Repeat reQuest (ARQ) scheme to improve the communication performances in EMI environments"--Abstract, page iii.

Converting Some Global Optimization Problems To Mixed Integer Linear Problems Using Piecewise Linear Approximations, Manish Kumar

Masters Theses

"Some global optimization problems are converted to mixed-integer linear problems (MILP) using piecewise-linear approximations in this thesis so that they can be solved using commercial MILP solvers, such as CPLEX. Special attention is given to approximating two-term log-sum functions, which appears frequently in generalized geometric programming problems. Numerical results indicate the proposed approach is sound and efficient"--Abstract, page iii.

Terahertz Data Processing For Standoff Detection Of Improvised Explosive Devices, Amit Bipin Shah

Masters Theses

"Improvised Explosive Devices (IEDs) are homemade, non-conventional explosive devices, which are used to destruct and incapacitate individuals and property. IEDs are becoming a popular weapon of attack among terrorists and insurgents due to their easy of making and capability to cause major damage. Hence, is has become necessary to develop efficient systems for detecting and disarming these devices. The Terahertz technology which uses electromagnetic radiations between 0.3 THz to 10 THz for imaging is one of the most recently developed detection techniques and is ideally suitable for detection of IEDs and similar devices. Although a lot of work has been …

Fast Sphere Decoder For Mimo Systems, Praveen G. Krishnan

Masters Theses

"This work focuses on variants of the conventional sphere decoding technique for Multi Input Multi Output (MIMO) systems. Space Time Block Codes (STBC) have emerged as a popular way of transmitting data over multiple antennas achieving the right balance between diversity and spatial multiplexing. The Maximum Likelihood (ML) technique is a conventional way of decoding the transmitted information from the received data, but at the cost of increased complexity. The sphere decoder algorithm is a sub-optimal decoding technique that is computationally efficient achieving a ;symbol error rate that is dependent on the initial radius of the sphere. In this thesis, …

Characterization Of Noise On Pdn And Electromagnetic Shielding, Sandeep K. R. Chandra

Masters Theses

"Modern FPGA and microprocessor have complex logic inside them, which draw current from the Power Distribution Network (PDN). This current drawn from the PDN creates disturbance on the PDN, which then propagates to other IC in different places on the Printed Circuit Board (PCB), and appears as a noise voltage. Ability to predict noise voltage at any point on the PCB gives a greater ability to carefully design the board and the PDN. In order to accurately predict the noise, it is important to accurately predict the current drawn and the transfer impedance from the source to the victim point. …

Identification Of Radial Streaming And Pseudopods In Dermoscopy Images, Sayali Prabhakar Deshpande

Masters Theses

"This thesis demonstrates an algorithm to identify the features of radial streaming and pseudopods found in dermoscopy images of malignant melanoma. The algorithm includes preprocessing images using the Principal Component Transform and an application of mathematical techniques to extract the desired features from the lesion image on the basis of color, size, shape, and orientation with respect to the lesion boundary. These identified features are further used to classify the lesion as malignant or benign. The proposed algorithm has produced a diagnostic accuracy of 90.50% for the training set of 31 malignant and 109 benign images and a diagnostic accuracy …

Synthesis And Characterization Of Platinum-Based Multi-Component Catalysts For Direct Methanol Fuel Cells, Li Ren

Masters Theses

"In the thesis work, Pt-based binary, ternary, quaternary alloy anode catalysts supported on sonochemically treated multi-walled carbon nanotubes (CNTs) were synthesized with ethylene glycol reduction of corresponding metal chloride salts. Inductively coupled plasma-mass spectroscopy (ICP-MS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM) were used for catalyst characterization. Cyclic voltammetry for methanol oxidation and CO stripping were used to evaluate the performance of the catalysts.

PtRu nanoparticles supported on CNTs (PtRu/CNT) were prepared under a series of pHs. It was found that the PtRu particle size, composition, and catalytic activity were all sensitive to the deposition …

Susceptibility Scanning System As Failure Analysis Tool For System Level Esd Problems, Giorgi Muchaidze

Masters Theses

"System level Electrostatic Discharges (ESDs) can lead to soft-errors (e.g., bit-errors, wrong resets). The goal of this project is to offer guidance in finding the root cause of soft-errors frequently observed using immunity scanning system. Immunity scanning is an increasingly adopted method for root cause analysis of system level immunity sensitivities. It allows localizing affected nets and ICs. At first a description of the ESD discharge process is given, which provides the necessary background for correctly analyzing ESD failures. Local scanning and in-circuit measurement techniques are expounded in this study. Further, it is shown how PCB scanning results can reveal …

Development Of A Geographic Information System-Based Virtual Geotechnical Database And Assessment Of Liquefaction Potential For The St. Louis Metropolitan Area, Jae-Won Chung

Doctoral Dissertations

"The St. Louis Metropolitan area is the focus the U.S. Geological Survey's Earthquake Hazard Program's plan for assessing and reducing the likely risks of an earthquake likely emanating from New Madrid Seismic Zone (NMSZ), which is the most active seismic zone in the Midwestern United States. The St. Louis Metropolitan area consists of three counties in Missouri and four in Illinois, which are divided by the state boundary along the Mississippi River. Both of the state's respective geological surveys have produced their own geologic maps and datasets, employing dissimilar geodata information and systems, with differing map units, map scales, and …

Architecting System Of Systems: Artificial Life Analysis Of Financial Market Behavior, Nil Hande Ergin

Doctoral Dissertations

"This research study focuses on developing a framework that can be utilized by system architects to understand the emergent behavior of system architectures. The objective is to design a framework that is modular and flexible in providing different ways of modeling sub-systems of System of Systems. At the same time, the framework should capture the adaptive behavior of the system since evolution is one of the key characteristics of System of Systems. Another objective is to design the framework so that humans can be incorporated into the analysis. The framework should help system architects understand the behavior as well as …