Engineering Commons^™

Quantitative Modeling Of Reliability And Survivability For Cyber-Physical Power Systems, Murtadha Nabeel Albasrawi

Masters Theses

"Critical infrastructure systems are increasingly reliant on cyber infrastructure that enables intelligent real-time control of physical components. This cyber infrastructure utilizes environmental and operational data to provide decision support intended to increase the efficacy and reliability of the system and facilitate mitigation of failure. Realistic imperfections, such as corrupt sensor data, software errors, or failed communication links can cause failure in a functional physical infrastructure, defying the purpose of intelligent control. As such, justifiable reliance on cyber-physical critical infrastructure is contingent on rigorous investigation of the effect of intelligent control, including modeling and simulation of failure propagation within the cyber-physical …

Hard-Switched Switched Capacitor Converter Design, Lukas Konstantin Müller

Masters Theses

"Switched capacitor (SC) converters are becoming quite popular for use in DC-DC power conversion. The concept of equivalent resistance in SC converters is frequently used to determine the conduction losses due to the load current. A variety of methodologies have been presented in the literature to predict the equivalent resistance in hard-switched SC converters. However, a majority of the methods described are difficult to apply to general SC converter topologies. Additionally, previous works have not considered all nonidealities in their analysis, such as switching losses or stray inductances. This work presents a generalized and easy to use model to determine …

The Description Of An Effective Sinkhole Investigation Approach: A Case Study Of Two Sites In Greene County, Missouri, Stanley Chinedu Nwokebuihe

Masters Theses

"Karst topographies pose danger to the environment. The associated gradual subsidence or sudden collapse of the ground can lead to loss of lives and damage to property. A sinkhole is the subsidence or collapse of the overburden into subsurface cavities. Sinkholes develop in different sizes, shapes and rates all over the world especially in areas where the bedrock can be dissolved by percolating slightly acidic surface water.

Different methods have been used to investigate sinkholes. Boring is the most common of these methods. But the boring technique is quite inefficient; it only provides information of the subsurface conditions at the …

Techno-Economic And Life-Cycle Modeling And Analysis Of Various Energy Storage Technologies Coupled With A Solar Photovoltaic Array, Brian Andrew Peterson

Masters Theses

"Renewable energies, such as wind and solar, are a growing piece of global energy consumption. The chief motivation to develop renewable energy is two-fold: reducing carbon dioxide emissions and reducing dependence on diminishing fossil fuel supplies. Energy storage is critical to the growth of renewable energy because it allows for renewably-generated electricity to be consumed at times when renewable sources are unavailable, and it also enhances power quality (maintaining voltage and frequency) on an electric grid which becomes increasingly unstable as more renewable energy is added. There are numerous means of storing energy with different advantages, but none has emerged …

Processing And Feature Analysis Of Atomic Force Microscopy Images, Xiao Pan

Masters Theses

"Atomic force microscopy (AFM) is a versatile and powerful tool for imaging and measuring small-scale objects such as nanoparticles, single molecules, semiconductor devices and living cells. The basic operation of an AFM can be to utilize a sharp cantilever tip that interacts with the sample surface and senses the local force between the tip and sample surface. Based on the physical interaction between the AFM and the small-scale object for image acquisition, there can be a number of artifacts, including curvature distortion (bowing effects), high-frequency or low-frequency noise, which may not be easily recognized by users accustomed to conventional microscopy. …

Improved Phase Shedding Technique In A Multiphase Converter System, Anagha Rayachoti

Masters Theses

"Multiphase converters are increasingly gaining prominence in the field of power electronics. The main advantage of a multiphase converter is its increased efficiency in comparison to a single phase converter. The one major drawback of a multiphase converter is its light load efficiency. Light load efficiency in multiphase converters is very poor when compared to single phase converters. Phase shedding is one of the approaches used to improve this light load efficiency but the transient output voltage response of the system shows large deviations during the process of phase change. This thesis proposes a new technique, called the ramp control …

An Effectiveness - Based Analysis Of Ground Coupled Heat Exchangers, Chou Shen

Masters Theses

"This thesis develops a theoretical framework, termed [Effectiveness] - BLU, to characterize the relation between temperatures, thermal contact and borehole length as it relates to the heat transfer processes in ground coupled heat exchangers used for ground source heat pump systems.

Borehole outflow temperature depends on the inflow temperature, the heat imposed on the borehole and the temperature history of the ground. In addition, variation of outflow temperature influences inflow temperature, even for the case of constant heat pump load. Because of this kind of feedback, the borehole inflow temperature may not be constant even with a fixed building load. …

Emi Investigation And Modeling Of A Flat Panel Display, Satyajeet Shinde

Masters Theses

"It is often important to carry out EMI analysis in the design phase of an electronic product to predict the radiated emissions. An EMI analysis is important to predict if the product complies with the FCC regulations as well as to gain an understanding of the noise coupling and radiation mechanisms. EMI analysis and prediction of radiated emissions in electronic products that have an electrically large chassis, pose a challenge due to the presence of multiple resonant structures and noise-coupling mechanisms.

The study focusses on the investigation of the main noise coupling mechanisms, the approach and methods used for the …

Bond Performance Of Recycled Aggregate Concrete, Amanda Renee Steele

Masters Theses

"In recent decades, engineers have sought a more sustainable method to dispose of concrete construction and demolition waste. One solution is to crush this waste concrete into a usable gradation for new concrete mixes. This not only reduces the amount of waste entering landfills but also alleviates the burden on existing sources of quality natural concrete aggregates. The objective of this study was to determine to effect of replacing coarse natural aggregates for recycled concrete aggregates (RCA) on the bond strength between deformed mild reinforcing steel and surrounding concrete. Two different RCA replacement levels were considered, 50% and 100%, and …

Two Driven Pile Load Tests For Use In Missouri Lrfd Guidelines, Matthew Garry Stuckmeyer

Masters Theses

"A static pile load test program was initiated by the Missouri Department of Transportation (MoDOT) to evaluate the use of pile load tests in Missouri LRFD guidelines. The program's approach involves two phases to achieve the appropriate levels of reliability for driven piles in the state of Missouri. This thesis focuses on the data collection efforts of Phase 1. Two quick static pile load tests were performed to failure on test piles in the Southeast Lowlands geologic region of Missouri. The piles were dynamically monitored during installation and subsequent restrike tests performed. The results of the static and dynamic pile …

Corrosion Resistance Of Enamel Coating Modified By Calcium Silicate And Sand Particle For Steel Reinforcement In Concrete, Fujian Tang

Masters Theses

"Porcelain enamel has stable chemical property in harsh environments such as high temperature, acid and alkaline, and it can also chemically react with substrate reinforcing steel resulting in improved adherence strength. In this study, the corrosion resistances of enamel coating modified by calcium silicate and sand particles, which are designed for improved bond strength with surrounding concrete, were investigated in 3.5 wt% NaCl solution. It consists of two papers that describe the results of the study.

The first paper investigates the corrosion behavior of enamel coating modified by calcium silicate applied to reinforcing steel bar in 3.5 wt% NaCl solution …

Studies Of Influencing Factors For Shale Gas Reservoir Performance, Jiaqi Wang

Masters Theses

"Shale gas resource plays a significant role in energy supply worldwide. For economic production of shale gas, technologies of horizontal well and hydraulic fracturing are used for shale gas reservoirs. Therefore, the productivity of the shale gas reservoirs will be influenced by both reservoir condition, and hydraulic fracture properties.

In this thesis, parameters that will influence shale gas production were classified into two categories: reservoir properties and hydraulic fracture properties. Published shale gas simulation studies were surveyed for determining the typical ranges of those properties. CMG-GEM was employed to finish the reservoir simulation work, and CMG-CMOST was used to complete …

Investigation Of Cased Wellbore Integrity In The Wabamun Area Sequestration Project, Benjamin Lee Weideman

Masters Theses

"Loss of cased wellbore integrity can cause many significant problems, including lost production, aquifer contamination, blowouts, and other environmental damage. The objective of this study is to conduct an analysis of the Wabamun Area Sequestration Project (WASP) to determine if wells in that area are suitable for CO₂ sequestration. This was done by conducting laboratory experiments on the common cement compositions found in the area, simulating the various conditions possible in a wellbore, and by analyzing three case studies from the WASP. The cases include two existing production wells and a proposed injection well specifically designed for CO₂ sequestration. This …

Computational Fluid Dynamics (Cfd) Modeling Of Proppant Transport In A Plug-And-Perf Completion With Different Perforation Phasing, Jinlin Zhang

Masters Theses

"Perf-and-plug is a completion technique commonly used in multistage fracturing. Fracture performance modeling assumes that fluid and proppant distributes uniformly among all perforations along the length of the wellbore in a plug and perf completion Crespo et al. (2012) has conducted a limited proppant flow experiment using a 63 foot stage, and three 0.42 inch, zero phased simulated perforations. His work demonstrates proppant does not distribute evenly, but the work is limited to a single perforation scheme.

In this study, Computational Fluid Dynamics (CFD) software has been used to simulate proppant transport and distribution in a single stage of a …

Additive Manufacturing Laser Deposition Of Ti-6al-4v For Aerospace Repair Application, Nanda Kumar Dey

Masters Theses

"Parts or products machined from high performance metals are very expensive, partly due to the processing complexities during manufacturing. Therefore, many high performance metal parts users, such as the aerospace industry, mold/die casting industry, heavy machinery consumers etc., extend the service of these damaged parts by employing repair or remanufacturing technology. The research objective is to use laser deposition and machining processes to repair titanium parts.

This thesis discusses a new way of approach for developing a repair process for Ti-6Al-4V for the aerospace industry using Laser Metal Deposition (LMD). The repairs were conducted in a multi-axis hybrid manufacturing systems …

Analysis And Implementation Of Pm Sampling Methodology Protocols To Aid In The Development Of An Arp (Aerospace Recommended Practice) For Aircraft Non-Volatile Pm Measurements, Brian Lowell Catron

Masters Theses

"Due to the growing concerns that particulate matter (PM) have on health and the environment, there is a need to include mass and number non-volatile PM measurements to current jet engine certification. This thesis looks at the necessary work required to help produce recommendations and perform background research to aid in the creation of an improved Aerospace Recommended Practice (ARP) (by the SAE E-31 Committee). This work addressed the following issues. The investigation began in the Missouri S&T Center of Excellence for Aerospace Particulate Emissions Reduction Research (COE) laboratory with an examination of the jet engine surrogate used, the miniCAST, …

Analysis Of A Ventilation Network In A Multiple Fans Limestone Mine, Ali Haghighat

Masters Theses

"As mining progresses the total resistance of an excavation is increased, the mine characteristic curve becomes steeper, and the operating point moves up the fan curve, reducing the total air quantity and increasing the system pressure. For multi-level ventilation networks with a number of fans the process can be tedious, and on a count of numerous dependent factors the optimal combination of fans is very hard to be achieved. The design of a ventilation network in conjunction with multi surface fans and booster fans entails a complex procedure.

The objective of this study is to provide a plan to improve …

Aspen Simulation Of Furfural And Hydroxymethylfurfural Production From Biomass, Zachary Daniel King

Masters Theses

"Biomass field liquefaction is a concept where green biomass is chemically treated to produce organic liquids using small-scale equipment in the field. If liquefaction occurs as the crop is harvested, the energy requirements for growing the biomass can be charged to the crop as if the biomass were left in the field. The energy in the organic liquid product is available at the expense of the energy required by the process. A simplified process was simulated using ASPEN to assess the energy production feasibility.

Acid catalyzed liquefaction of cellulose and hemicellulose solids produces furfural and hydroxymethylfurfural (HMF). The simulation assumed …

Assessment Of Contributing Factors To The Reduction Of Diarrhea In Rural Communities Of Para, Brazil, Lee Voth-Gaeddert

Masters Theses

"In developing communities the occurrence of diarrhea has been reported at elevated levels as compared to those communities in more developed regions. Diarrheal diseases were linked to over one million deaths in 2012 throughout the world. While multiple pathways are present for the transmission of diarrheal diseases, water has been the focus for many aid organizations. Point-of-use (POU) water treatment methods are a common tool used by aid organizations in efforts to provide potable water. The CAWST biosand filter is a POU tool that has shown removal effectiveness of pathogenic microorganisms ranging from 90-99%. However, minimal literature was found that …

Determination Of Minor And Trace Elements Concentration In Kidney Stones Using Elemental Analysis Techniques, Anjali Srivastava

Masters Theses

"The determination of accurate material composition of a kidney stone is crucial for understanding the formation of the kidney stone as well as for preventive therapeutic strategies. Radiations probing instrumental activation analysis techniques are excellent tools for identification of involved materials present in the kidney stone. The X-ray fluorescence (XRF) and neutron activation analysis (NAA) experiments were performed and different kidney stones were analyzed. The interactions of X-ray photons and neutrons with matter are complementary in nature, resulting in distinctly different materials detection. This is the first approach to utilize combined X-ray fluorescence and neutron activation analysis for a comprehensive …

Cervical Cancer Histology Image Feature Extraction And Classification, Peng Guo

Masters Theses

"Cervical cancer, the second most common cancer affecting women worldwide and the most common in developing countries can be cured if detected early and treated. Expert pathologists routinely visually examine histology slides for cervix tissue abnormality assessment. In previous research, an automated, localized, fusion-based approach was investigated for classifying squamous epithelium into Normal, CIN1, CIN2, and CIN3 grades of cervical intraepithelial neoplasia (CIN) based on image analysis of 62 digitized histology images obtained through the National Library of Medicine. In this research, CIN grade assessments from two pathologists are analyzed and are used to facilitate atypical cell concentration feature development …

Determining And Mitigating The Effects Of Firing A Linear Shaped Charge Under Water, Brian Burch

Masters Theses

"When fired under water, a Linear Shaped Charge (LSC) does not penetrate a steel target as well as in air. This lack of performance has been a problem for shaped charge manufacturers and their clients. It was obvious that this degradation of performance is due to water having a higher density than air and water being incompressible compared to air. This study aimed to better determine how the water was affecting the LSC and to provide a method of mitigation.

LSCs of different sizes were submerged under water and fired through the water with and without a target. It was …

Effect And Interactions Of Commercial Additives And Chloride Ion In Copper Electrowinning, Wenyuan Cui

Masters Theses

"This thesis is to understand and compare the effects and interactions of modified polysaccharide (HydroStar), polyacrylamide (Cyquest N-900) and chloride ion on copper electrowinning. A study of the nucleation and growth was conducted in a synthetic electrolyte (40 g/L Cu, 160 g/L H₂SO₄, 20 mg/L Cl-) with the addition of HydroStar or Cyquest N-900 using potential step measurements. The current responses generated were compared to theoretical models of nucleation and growth mechanisms. The nucleation and growth mechanism changed as function of potential and the presence of organic additives. The nucleation and growth mechanisms were confirmed using scanning electron microscopy (SEM). …

Effects Of Indentation Speed And Water Saturation Level On The Behavior Of Roubidoux Sandstone, Azupuri Ayerikujei Kaba

Masters Theses

"The experiment conducted in this research was to determine the behavior of a porous rock under an indenter. To investigate this, medium-grained sandstone was subjected to a series of indentation tests. These tests were conducted under both dry and saturated conditions using a rounded conical indenter. In addition, tests were conducted at different indentation speeds. The test results were used to calculate the mechanical specific energy (SE) and specific penetration (SP). The porewater pressure evolution in the saturated sample was also monitored.

The tests and subsequent analyses reveal that saturation did not affect the specific energy when the indentation rate …

Gold-Magnetite Nanoparticle-Biomolecule Conjugates: Synthesis, Properties And Toxicity Studies, Akshay Pariti

Masters Theses

"This thesis study focuses on synthesizing and characterizing gold-magnetite optically active magnetic nanoparticle and its conjugation with biomolecules for biomedical applications, especially magnetic fluid hyperthermia treatment for cancerous tissue. Gold nanoparticles have already displayed their potential in the biomedical field. They exhibit excellent optical properties and possess strong surface chemistry which renders them suitable for various biomolecule attachments. Studies have showed gold nanoparticles to be a perfect biocompatible vector. However, clinical trials for gold mediated drug delivery and treatment studied in rat models identified some problems. Of these problems, the low retention time in bloodstream and inability to maneuver externally …

Methamphetamine Absorption By Skin Oils: Accumulated Mass, Partition Coefficients And The Influence Of Fatty Acids, Kristia Parker

Masters Theses

"Occupants of former methamphetamine laboratories, often residences, may experience increased exposure through the accumulation of the methamphetamine in skin oil. The objectives of this study were to determine equilibrium partition coefficients of vapor-phase methamphetamine with artificial skin oil (ASO), artificial skin oil without fatty acids and real skin oil. A 10 L flow through stainless-steel chamber and in-line filter holders were used to expose skin-oil coated filters to vapor-phase methamphetamine at concentrations ranging from 12 ppb to 159 ppb and samples were analyzed for exposure time periods from 2 hours to 60 days. For a low vapor-phase methamphetamine concentration range …

Microwave Assisted Reconstruction Of Optical Interferograms For Distributed Fiber Optics Sensing & Characterization Of Pcb Dielectric Properties Using Two Striplines On The Same Board, Lei Hua

Masters Theses

"A new concept, the microwave-assisted reconstruction of an optical interferogram for distributed sensing, was developed to resolve both the position and reflectivity of each sensor along an optical fiber. This approach involves sending a microwave-modulated optical signal through cascaded fiber optic interferometers. The optical spectrum of each sensor can be reconstructed by sweeping the optical wavelength and detecting the modulation signal. A series of cascaded fiber optic extrinsic Fabry-Perot interferometric sensors was used to prove the concept. The microwave-reconstructed interferogram matched well with those recorded individually from a traditional optical spectrometer. The application of distributed strain measurement was also investigated. …

Performance Analysis Of Zero Forcing And Minimum Mean Square Error Equalizers On Multiple Input Multiple Output System On A Spinning Vehicle, Aditya Kulkarni

Masters Theses

"Channel equalizers based on minimum mean square error (MMSE) and zero forcing (ZF) criteria have been formulated for a general scalable multiple input multiple output (MIMO) system and implemented for a 2x2 MIMO system with spatial multiplexing (SM) for Rayleigh channel associated with additive white Gaussian noise. A model to emulate transmitters and receivers on a spinning vehicle has been developed. A transceiver based on the BLAST architecture is developed in this work. A mathematical framework to explain the behavior of the ZF and MMSE equalizers is formulated. The performance of the equalizers has been validated for a case with …

Shielding Effectiveness (Se) Measurement For Maxair Waveguide Panel, Lossy Material Evaluation By Laptop Application, Xiao Li

Masters Theses

"The first part of the thesis presents the EM shielding effectiveness (SE) measurement of new kind of waveguide panel, MaxAir, which based on metal coating technology. SE Measurement tell the SE performance of MaxAir compared to the traditional metal waveguide panel. In terms of good features such as lower price, less weight, MaxAir could replace traditional waveguide panel in some applications by its SE results. There are two SE measurement methods are performed for MaxAir panel, both of them based on reverberation chamber. Measured SE for several MaxAir panel samples in different cell dimension and coating configuration. By the Measured …

Experimental Investigation Of The Pebble Bed Structure By Using Gamma Ray Tomography, Fadha Shakir Ahmed

Masters Theses

"Pebble Bed Reactors offer a future for new nuclear energy plants. They are small, inherently safe, and can be competitive with fossil fuels. The fuel forms a randomly stacked pebble with non-uniform fuel densities. The thermal-mechanical behavior of pebble bed reactor core is depends strongly on the spatial variation of packing fraction in the bed and in particular on the number of contacts between pebbles, and between the pebbles and the blanket walls. To investigate these effects, experimental data to characterize bed structure are needed along with other numerical simulation and computational tools for validation.

In this study, a powerful …