Digital Commons Network^™

Computer Aided Detection Of Oral Lesions On Ct Images, Shaikat Mahmood Galib

Masters Theses

"Oral lesions are important findings on computed tomography images. They are difficult to detect on CT images because of low contrast, arbitrary orientation of objects, complicated topology and lack of clear lines indicating lesions. In this thesis, a fully automatic method to detect oral lesions from dental CT images is proposed to identify (1) Closed boundary lesions and (2) Bone deformation lesions. Two algorithms were developed to recognize these two types of lesions, which cover most of the lesion types that can be found on CT images. The results were validated using a dataset of 52 patients. Using non training …

Comprehensive Benefits Of Green Roofs, Madison R. Gibler

Masters Theses

"Green infrastructure uses vegetation, soils, and natural processes to manage water and create healthier urban environments, providing traditional roof services and alternative stormwater management technologies. Other benefits and impacts are not yet fully understood or valued. Research conducted assesses specific stormwater benefits of green roofs, providing information on nutrient leaching from media; and analyzes potential energy benefits through side-by-side comparisons of full-scale white, traditional black rubber, and green roofs in the mid-continent Missouri climate. Roofing media selection impacted leaching of nutrients, suspended solids, and organic carbon from the tested green roof media. Thermal properties were investigated at the building level, …

Characterizing The Influence Of Carbon On The Flowrate And Disinfection Efficacy Of Household Ceramic Water Filters, Jessie Yvonne Hahn

Masters Theses

"Drinking water contamination is a major cause of disease in developing countries. Point of Use (POU) water treatment technologies generally have low initial cost and allow rapid availability of improved water. Ceramic pot filters (CPFs) are a POU water source treatment technology which filter water by gravity through a porous ceramic media. Some filters in use contain carbon remnants left from the fugitive pore former as a dark carbon core. Using disk-shaped experimental ceramic filters produced in the lab to have varying levels of carbon, the percent carbon present was measured and a visual analysis method was developed to determine …

Esd Event Locator, Syed Abrar Ul Huq

Masters Theses

"Electrostatic Discharge (ESD) presents one of the most common threats to electronic systems especially in the cases of high-speed digital systems. ESD event locator systems have been designed to determine the location of the source of the ESD event using different techniques. One such method of determining the origin of the ESD event, is the use of four antennas and a high-speed Analog to Digital Converter (ADC) system to capture the ESD events.

This thesis presents such an implementation which deals with the design of an analog front-end to a fast TI LM97600 ADC and a Virtex-5 Field-Programmable Gated Array …

Model Predictive Current Control Of Switched Reluctance Motor With Inductance Auto-Calibration, Xin Li

Masters Theses

"The thesis is composed of three papers, which investigate the application of Model Predictive Controller (MPC) for current control of Switched Reluctance Motor (SRM). Since the conventional hysteresis current control method is not suitable for high power SRM drive system with low inductance and limited switching frequency, MPC is a promising alternative approach for this application. The proposed MPC can cope with the measurement noise as well as uncertainties within the machine inductance profile. In the first paper, a MPC current control method for Double-Stator Switched Reluctance Motor (DSSRM) drives is presented. A direct adaptive estimator is incorporated to follow …

A Study Into Improving Transformer Loading Capability Beyond Nameplate Rating, Aakanksha Pasricha

Masters Theses

"Utilities are becoming increasingly interested in the prospect of overloading the transformers beyond the nameplate rating to meet the increased demand for power as it may be more economically viable than installing a new transformer. The safety of the transformer has to be ensured while overloading it and hence there is a maximum loading beyond which the transformer should not be overloaded. A study has been performed on 38 transformer units and the factors that limit their overloading capability have been analyzed. Ancillary equipment ratings were found to be the most prominent limiting factor. Several case studies and evaluation results …

Laser Surface And Sub-Surface Repair During Metal Additive Manufacturing, Prudvi Teja Ravi

Masters Theses

"This study examines the use of laser surface treatment to repair surface and subsurface defects. Numerical analysis was performed on laser surface melting using Gaussian heat distribution equations to analyze the depth of the melt pool created by the phenomena. Concurrently, a process map was developed with a planned set of experiments by varying the ranges of laser power and travel speed to determine the dimensions of the melt pool across the gamut. The data generated from both the process studies and the numerical analysis was then used to determine the ideal operating ranges of the process parameters to repair …

Spatial And Temporal Modulation Of Heat Source Using Light Modulator For Advanced Thermography, Arvindvivek Ravichandran

Masters Theses

"Thermography is a Non-Destructive Testing (NDT) method that has found increasing use in industry and research. It has the advantages of being non-contact and be able to interrogate a large surface simultaneously. Active thermography using flash lamps as heat source has been demonstrated for identifying blind holes and delamination in composites. Despite these advancements, active thermographic approach fails to defects like cracks. Under uniform illumination heat flow is predominantly 1D and can easily circumvent a narrow feature. This can be overcome by using a focused light/laser source onto the surface to impose a 3D heat flux. The disadvantage is that …

Computer Aided Diagnosis Of Oral Cancer: Using Time-Step Ct Images, Jonathan T. Scott

Masters Theses

"In medical imaging it is a very common practice to use a technique known as Time-Step imaging in patients who might develop cancer. Time-Step imaging it a very powerful technique, however it can lead to unmanageable amounts of image data. Previously the only way to search all of this data was to manually look through all of the files. This had to be done by trained professionals who knew what to look for within the images and make a judgment about the patient based on the images. This paper discusses the development of an algorithm to have a computer search …

Detection And Removal Of Emerging Environmental Contaminants, Ruipu Mu

Doctoral Dissertations

"Water is a very crucial natural resource for human. The increasing number of contaminants detected in water bodies has drawn considerable increasing attention over the last decade. There are numerous emerging environmental contaminants which may cause serious health issues. The recent occurrence studies of these contaminants show both industrial and household activity introduction of chemicals into water resources. These various sources result in a large variety of chemicals such as explosives, pharmaceutical and personal care products (PPCPs) and disinfection byproducts detected in water worldwide. Due to the relatively low contaminant concentrations, development of new and improved detection methods along with …

Estimation Of Tip-Sample Force In Tapping Mode Atomic Force Microscopy Using Neural-Network And Repetitive Control Approaches, Alireza Toghraee

Masters Theses

"Atomic Force Microscopy is one of the most powerful tools for imaging, measuring and manipulating materials at nanometer scale. Among different modes of AFM, tapping mode, in which the oscillating tip touches the sample periodically, is most common mode. During the tip approach and retract, the tip interacts with sample and experiences different force regimes. This tip-sample interaction force contains information about the sample topology, material properties and tip geometry. However, quantitative measurement of the time-varying tip-sample interaction forcing function is challenging in the tapping mode because of the combined dynamic complexities of the cantilever and nonlinear complexity of the …

Factors Affecting The Heat Transfer During The Dip Testing Of Potential Third Generation Advanced High Strength Steels, Kramer Michael Pursell

Masters Theses

"A dip tester was designed and built at Missouri University of Science and Technology to test the effects of the primary alloying elements (Mn, Si, and Al) of Fe-Mn-Al-Si-C type 3rd generation advanced high strength steel (AHSS) alloys, dipping superheat, and dipping speed on the heat transfer during rapid solidification. The difficulties associated with casting 3rd generation AHSS were compiled as well to serve as a best-practices guide. An extensive list of potential 3rd generation AHSS alloys was developed and tested, and the effects of various dip testing parameters were examined.

Manganese was found to increase the heat flux by …

Aerial Vehicle Trajectory Design For Spatio-Temporal Task Satisfaction And Aggregation Based On Utility Metric, Amarender Reddy Mekala

Masters Theses

"Flight trajectories are mainly designed in order to make sure that the aerial vehicle reaches the destination point from the start point. In addition to that, the flight path is designed in such a way that the flight avoids dangerous zones and the maneuvers required for the path are practically feasible for the flight.

This thesis focuses on the aerial vehicle trajectory generation passing through a set of pre-defined way points while satisfying the task points sent by the ground base station in between the way points. Each specified waypoint is reached exactly at the specified location and time. Intermediate …

In Vitro Study Of Wound-Healing Capabilities Of Bioactive Glass Fibers Under Various Culture Conditions, Sisi Chen

Masters Theses

"Bioactive borate glass has been recognized to have both hard and soft tissue repair and regeneration capabilities through stimulating both osteogenesis and angiogenesis. However, the underlying physiological and cellular mechanism behind this function remains unclear. In this study, in vitro dynamic flow modules were designed to mimic the micro-environment near the vascular depletion and hyperplasia area in wound-healing regions, and were used to investigate the biocompatibility and functionality of borate glass nano-/micro-fibers. Glass-cell interactions were investigated either by dosing fibers to the upstream of or co-cultured with cells, and two types of borate glasses (with or without CuO/ZnO doped were …

Damage Detection Through Acoustic Emission Of Fracture Processes In Concrete Masonry Units, John Alexander Cain

Masters Theses

"Masonry structures are vulnerable to earthquakes; their brittleness and discontinuous formation make them susceptible to collapse. In the event of an emergency, this could be detrimental and perhaps fatal. The area of Structural Health Monitoring (SHM) is focused on understanding the behavior of structures for the sake of safety and predicting their longevity. One applicable technique to monitor this behavior is Acoustic Emission (AE). Acoustic Emissions are transient elastic waves released as microcracks nucleate from stress intensities, coalesce into cracks and then accumulate as damage. AE monitoring is a favorable method because it is capable of detecting cracking from within …

Characterization Of Bending Fatigue Mini-Specimens For Nuclear Materials, Ahmed Suliman R. Haidyrah

Doctoral Dissertations

"New materials with superior radiation and corrosion resistance are needed to improve the economy and performance of current nuclear reactors as well as future nuclear reactors. Measurement of mechanical properties of the material of equipment is required to estimate its safe operating life. Studying fatigue of irradiated specimens is challenging due to space limitation in research reactors (e.g. ATR). The mini-specimen bending fatigue (Krouse-type) of nuclear materials was used to study fatigue properties and compare the obtained results with that of reference data of full size specimen. These Krouse-type were made of austenitic SS304, SS316, HT9 ferritic martensitic steel, and …

Seismological Investigation Of The Okavango Rift, Botswana, Youqiang Yu

Doctoral Dissertations

The mechanisms of rifting have been intensively investigated using geological and geophysical techniques beneath mature rift zones. However, current understanding on the earliest stages of rifting is seriously limited. Here we employ recently archived data from 17 broadband seismic stations traversing northern Botswana to conduct the first shear wave splitting and mantle transition zone (MTZ) studies within the Okavango Rift Zone (ORZ). The ORZ is an incipient continental rift situated at the terminal of the southwestern branch of the East African Rift System. The resulting normal MTZ thickness and consistently rift-parallel fast polarizations imply an absence of significant thermal anomalies …

Numerical And Field Data Analysis Of Drill Stem Vibration, Mohammed Fayez Al Dushaishi

Doctoral Dissertations

"Drill stem vibration is a major cause of premature failure of drill stem components and drilling inefficiency. In severe cases, drill stem vibration may lead to wellbore instability that could lead to increased operational cost. Drill stem vibrations are affected by design decisions and the drilling environment. Examples are; bottom hole assembly configurations, selection of operational parameters, and frequent changes in lithology. Vibration modeling, analysis of vibration data, and specialized vibration reduction tools are methods in use to prevent and mitigate severe vibrations.

A drill stem vibration model was created using nonlinear strain formulation which couples the axial, lateral and …

Directional Thermal Emission From A Leaky-Wave Frequency-Selective Surface, Edward C. Kinzel, J. C. Ginn, L. A. Florence, B. A. Lail, G. D. Boreman

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.

Big Data -- A 21st Century Science Maginot Line? No-Boundary Thinking: Shifting From The Big Data Paradigm, Xiuzhen Huang, Steven F. Jennings, Barry Bruce, Alison Buchan, Liming Cai, Pengyin Chen, Carole Cramer, Weihua Guan, Uwe Kk Hilgert, Hongmei Jiang, Zenglu Li, Gail Mcclure, Donald F. Mcmullen, Bindu Nanduri, Andy Perkins, Bhanu Rekepalli, Saeed Salem, Jennifer Specker, Karl Walker, Donald C. Wunsch, Donghai Xiong, Shuzhong Zhang, Yu Zhang, Zhongming Zhao, Jason H. Moore

Electrical and Computer Engineering Faculty Research & Creative Works

Whether your interests lie in scientific arenas, the corporate world, or in government, you have certainly heard the praises of big data: Big data will give you new insights, allow you to become more efficient, and/or will solve your problems. While big data has had some outstanding successes, many are now beginning to see that it is not the Silver Bullet that it has been touted to be. Here our main concern is the overall impact of big data; the current manifestation of big data is constructing a Maginot Line in science in the 21st century. Big data is not …

Future Internet Resilience For Massive Failures, Yufei Cheng, Egemen K. Çetinkaya, James P. G. Sterbenz

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Simulation Of Dpm Distribution In A Long Single Entry With Buoyancy Effect, Yi Zheng, Magesh Thiruvengadam, Hai Lan, Jerry Tien C.

Mining Engineering Faculty Research & Creative Works

Diesel particulate matter (DPM) is considered carcinogenic after prolonged exposure. With more diesel-powered equipment used in underground mines, miners' exposure to DPM has become an increasing concern. This paper used computational fluid dynamics (CFD) method to study DPM distribution based on an experiment conducted by the Diesel Emissions Evaluation Program (DEEP) in Canada. Twenty-four cases were simulated where the emissions from both truck and load-haul-dumps (LHDs) were examined. Each vehicle was placed in two stream wise locations, and the vehicles were oriented either facing or with the rear end toward the main fresh airflow. A species transport model with buoyancy …

Composition- And Pressure-Induced Ferroelectric To Antiferroelectric Phase Transitions In Sm-Doped Bifeo₃ System, Fei Xue, Linyun Liang, Yijia Gu, Ichiro Takeuchi, Sergei V. Kalinin, Long-Qing Chen

Materials Science and Engineering Faculty Research & Creative Works

A three-dimensional phenomenological model is proposed to describe both ferroelectricity and antiferroelectricity based on the Ginzburg-Landau-Devonshire theory. Its application to the multiferroic Sm-doped BiFeO₃ system describes the temperature-, pressure-, and composition-induced ferroelectric to antiferroelectric phase transitions. The constructed temperature-composition and temperature-pressure phase diagrams show that compressive hydrostatic pressure and Sm doping have similar effects on the ferroelectric and antiferroelectric phase transitions. It is also indicated from the temperature-pressure phase diagram that the experimentally observed phase of BiFeO₃ under the hydrostatic pressure from 3 GPa to 10 GPa is a PbZrO₃-like antiferroelectric phase.

Nanoscale Mechanical Switching Of Ferroelectric Polarization Via Flexoelectricity, Yijia Gu, Zijian Hong, Jason Britson, Long-Qing Chen

Materials Science and Engineering Faculty Research & Creative Works

Flexoelectric coefficient is a fourth-rank tensor arising from the coupling between strain gradient and electric polarization and thus exists in all crystals. It is generally ignored for macroscopic crystals due to its small magnitude. However, at the nanoscale, flexoelectric contributions may become significant and can potentially be utilized for device applications. Using the phase-field method, we study the mechanical switching of electric polarization in ferroelectric thin films by a strain gradient created via an atomic force microscope tip. Our simulation results show good agreement with existing experimental observations. We examine the competition between the piezoelectric and flexoelectric effects and provide …

Modelling Robustness Of Critical Infrastructure Networks, Srinath Pinnaka, Rajgopal Yarlagadda, Egemen K. Çetinkaya

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Network Attack Experimentation Using Openflow-Enabled Geni Testbed, Mani Chaitanya Gorla, Venu Madhav Kamaraju, Egemen K. Çetinkaya

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Performance Oriented Adaptive Architectures With Guaranteed Bounds, Benjamin Gruenwald, Tansel Yucelen, Mario Fravolini

Mechanical and Aerospace Engineering Faculty Research & Creative Works

While adaptive control has been used in numerous applications to achieve given system stabilization or command following criteria, the ability to obtain a predictable transient performance is a challenging problem when there is no a priori knowledge about system uncertainties (e.g., their upper bounds and/or domains). In order to address this problem, a new method is presented in [1, 2] utilizing artificial basis functions in the update law of an adaptive control design. This approach is predicated on a gradient minimization procedure and achieves a predictable transient performance without inducing oscillations in the system response as the constant gain due …

Efficient Calculation Of Large Finite Periodic Structures Based On Surface Wave Analysis, Xiaoyan Y.Z. Xiong, Ling Ling Meng, Li (Lijun) Jun Jiang, Wei E.I. Sha, Fan Yang

Electrical and Computer Engineering Faculty Research & Creative Works

The electromagnetic modeling of practical finite periodic structures is a topic of growing interest. Due to the truncation of infinite periodic structures, surface waves will be excited and localized near discontinuous interfaces leading to the edge effect. In this work, surface waves are numerically extracted and their magnitudes and decay rates are analyzed for different materials and geometries. Based on the exponential decay of the surface wave, a novel method is developed by connecting the solution to the large finite array problem with that to a relatively small one to achieve low complexity and memory consumption. The method numerically reconstructs …

An Efficient Linear Precoding Algorithm For Energy Harvesting Transmitter With Finite-Alphabet Inputs And Instantaneous Csi, Xiaodong Zhu, Weiliang Zeng, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

This paper investigates the precoder design in multiple-input multiple-output (MIMO) systems with energy harvester. The objective is to maximize the sum of mutual information (MI) over multiple time slots with causal knowledge of energy arrivals. Different from existing works, the system is considered with finite-alphabet inputs, and the transmitter is assumed to know not only the statistical channel state information (CSI) but also the instantaneous CSI of the current time slot at the beginning of each time slot. The optimal precoder design leads to an intractable multi- dimensional matrix optimization problem. We show that this difficult optimization problem can be …

Investigation Of Thermoelectric Properties Of P-Type Gan Thin Films, Bahadir Kucukgok, Babar Hussain, Chuanle Zhou, Ian T. Ferguson, Na Lu

Electrical and Computer Engineering Faculty Research & Creative Works

GaN and its alloys are promising candidates for high temperature thermoelectric (TE) materials due to their high Seebeck coefficient and high thermal and mechanical stability. Moreover, these materials can overcome the toxicity concern of current Te-based TE materials, such as BI₂Te₃ and PbTe. These materials have recently shown a higher Seebeck coefficient than that of SiGe in high temperature region because their large bandgap characteristic eliminates the bipolar conduction. In this study, we report the room temperature thermoelectric properties of p-type Mg doped GaN, grown by metalorganic chemical vapor deposition (MOCVD) on sapphire substrate with various carrier …