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An Analytical Pressure Model To Guide Downhole Sensor Placement For Carbon Dioxide Sequestration Monitoring, Yilin Mao Jan 2014

An Analytical Pressure Model To Guide Downhole Sensor Placement For Carbon Dioxide Sequestration Monitoring, Yilin Mao

Masters Theses

"Injecting CO₂ into saline aquifers is currently the most viable approach to mitigate global greenhouse gas effect. Various monitoring techniques are required to achieve 99% accuracy in determining the location of the injected CO₂ plume. Sensor locations are critical to the monitoring quality necessary to meet this requirement but have scarcely been discussed. The pressure profile needs to be modeled accurately at the initial stage of CO₂ injection to guide sensor locations. The objective of this thesis was to develop an analytical solution for CO₂ sequestration based on time and distance. This will guide the locations of downhole pressure sensors …


Thermal Properties Of Zirconium Diboride - Transition Metal Boride Solid Solutions, Devon Lee Mcclane Jan 2014

Thermal Properties Of Zirconium Diboride - Transition Metal Boride Solid Solutions, Devon Lee Mcclane

Masters Theses

"This research focuses on the thermal properties of zirconium diboride (ZrB₂) based ceramics. The overall goal was to improve the understanding of how different transition metal (TM) additives influence thermal transport in ZrB₂. To achieve this, ZrB₂ with 0.5 wt% carbon, and 3 mol% of individual transition metal borides, was densified by hot-press sintering. The transition metals that were investigated were: Y, Ti, Hf, V, Nb, Ta, Cr, Mo, W, and Re. The room temperature thermal diffusivities of the compositions ranged from 0.331 cm²/s for nominally pure ZrB₂ to 0.105 cm²/s for (Zr,Cr)B₂ and converged around 0.155cm²/s at higher temperatures …


Hard-Switched Switched Capacitor Converter Design, Lukas Konstantin Müller Jan 2014

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 …


Bridge Deck Condition Assessment Using Destructive And Nondestructive Methods, Brandon Tyler Goodwin Jan 2014

Bridge Deck Condition Assessment Using Destructive And Nondestructive Methods, Brandon Tyler Goodwin

Masters Theses

"This study investigates two bridge decks in the state of Missouri using both nondestructive and destructive testing methods. The Missouri Department of Transportation (MoDOT) is responsible for the monitoring and maintenance of over 10,000 bridges. Currently monitoring of these bridges includes a comprehensive visual inspection. In this study, ground-coupled ground penetrating radar (GPR) is used to estimate deterioration, along with other traditional methods, including visual inspection, and core evaluation. Extracted core samples were carefully examined, and the volume of permeable pore space was determined for each core. After the initial investigation, the two bridges underwent rehabilitation using hydrodemolition as a …


Fair And Optimal Resource Allocation In Wireless Sensor Networks, Vinodhini Ravikumar Jan 2014

Fair And Optimal Resource Allocation In Wireless Sensor Networks, Vinodhini Ravikumar

Masters Theses

"There is a large amount of research in wireless networks focuses on optimization of either network routing and power control alone. In contrast, this work aims at jointly optimizing the transmission power and routing path selection in order to optimize allocation of resources in interference constrained wireless environment. Moreover, we consider a multipath routing where multiple alternative paths are employed to transmit data between the end nodes. One of modern communication techniques that it applies to a network coding, though not explicitly implemented in this work. The proposed approach is first analyzed theoretically using Lagrangian optimization for a three-node scenario. …


The Description Of An Effective Sinkhole Investigation Approach: A Case Study Of Two Sites In Greene County, Missouri, Stanley Chinedu Nwokebuihe Jan 2014

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 …


Bond Performance Of Recycled Aggregate Concrete, Amanda Renee Steele Jan 2014

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 …


Efficient Data Access In Mobile Cloud Computing, Siva Naga Venkata Chaitanya Vemulapalli Jan 2014

Efficient Data Access In Mobile Cloud Computing, Siva Naga Venkata Chaitanya Vemulapalli

Masters Theses

"This thesis focuses on the development of efficient data transfer mechanism among mobile devices using Mobile cloud computing paradigm. Mobile cloud computing is coupling of mobile computing and cloud computing. In the Mobile cloud computing paradigm, users connect to cloud service providers over the Internet and leverage the cloud resources to perform their processing, storage and communication tasks. In this thesis, the focus is on communication tasks among mobile devices performed using Mobile cloud computing paradigm.

Communication or data sharing among mobile devices is often limited by proximity of the devices. This limitation can be removed by employing Mobile cloud …


Investigation Of Cased Wellbore Integrity In The Wabamun Area Sequestration Project, Benjamin Lee Weideman Jan 2014

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 …


A Remote Sensing Investigation Of Elevated Sub-Horizontal Topographic Surfaces In The Wichita Mountains, Oklahoma, Liang Xue Jan 2014

A Remote Sensing Investigation Of Elevated Sub-Horizontal Topographic Surfaces In The Wichita Mountains, Oklahoma, Liang Xue

Masters Theses

"Multiple elevated horizontal to sub-horizontal topographic surfaces are present in the Wichita Mountains, Oklahoma. Elevated topographic surfaces, developed primarily on granite bedrock with gentle slopes of 0.5 to 7⁰,were investigated using 1) Digital Elevation Models (DEMs) extracted from NAD 27 UTM coordinates, 2) Google Earth imagery, and 3) USGS topographic maps. In the western Wichita Mountains prominent topographic surfaces at elevations of 720 ± 5 m, 685 ± 5 m, and 660 ± 5 m are well preserved on at least four different mountains (e.g., Solder's Peak, King Mt.) and can be correlated with similar surfaces on at least seven …


Determination Of Minor And Trace Elements Concentration In Kidney Stones Using Elemental Analysis Techniques, Anjali Srivastava Jan 2014

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 …


Pn Anisotropy Tomography Of The Colorado Plateau And Adjacent Areas, Shengyao Cheng Jan 2014

Pn Anisotropy Tomography Of The Colorado Plateau And Adjacent Areas, Shengyao Cheng

Masters Theses

"The Pn tomography method utilizes seismic waves that refract along the Moho interface to perform inversion in order to investigate velocity anomalies and seismic anisotropy in the uppermost mantle. Results from Pn tomography can provide important information about the composition, temperature, and tectonic processes beneath the study area. Over the past decades, numerous seismic and geologic studies have been conducted in the Colorado Plateau and its adjacent areas to reveal crustal and mantle structures and processes responsible for the diverse surface geological features and tectonic events that have occurred in this area. To investigate lateral variations in the uppermost mantle …


Privacy Preservation Using Spherical Chord, Doyal Tapan Mukherjee Jan 2014

Privacy Preservation Using Spherical Chord, Doyal Tapan Mukherjee

Masters Theses

"Structured overlay networks are primarily used in data storage and data lookup, but they are vulnerable against many kinds of attacks. Within the realm of security, overlay networks have demonstrated applicability in providing privacy, availability, integrity, along with scalability. The thesis first analyses the Chord and the SALSA protocols which are organized in structured overlays to provide data with a certain degree of privacy, and then defines a new protocol called Spherical Chord which provides data lookup with privacy, while also being scalable, and addresses critical existing weaknesses in Chord and SALSA protocols. Spherical Chord is a variant of the …


Data Mining And Statistical Analysis Of Completions In The Canadian Montney Formation, Mustafa Adil Al-Alwani Jan 2014

Data Mining And Statistical Analysis Of Completions In The Canadian Montney Formation, Mustafa Adil Al-Alwani

Masters Theses

"This thesis documents a data-mining study and statistical analysis of well completion methods and their impact on production for more than 3300 horizontal wells in the Canadian Montney resource play.

The statistical software JMP is used to analyze well and production data for both horizontal Montney gas and oil wells, examining production trends with changes in completion parameters, such as the type of completion, fluid volume pumped, proppant load, number of fracture stages and completion costs. The analysis also provides a general understanding of average treatment characteristics, and how completions have changed with time for the Montney play.

Among the …


Effects Of Grain Properties And Compaction On Single-Tool Normal Indentation Of Granular Materials, Dennis Chieze Duru Jan 2014

Effects Of Grain Properties And Compaction On Single-Tool Normal Indentation Of Granular Materials, Dennis Chieze Duru

Masters Theses

"The behavior of three granular materials; filter sand, crushed garnet, and shale cutting, were investigated in an effort to evaluate the effect of grain size and shape, and material compaction under single tool load-indentation test. Force-penetration data was collected continuously through the end of each test and specific energy and specific penetration was calculated from the data.

Grain size and compaction affected the force penetration behavior. The higher the grain size, the more the fluctuation in the force of penetration. In addition, compaction reduces the force fluctuation in the fine aggregate grains, but increases the magnitude of the force fluctuations …


Characterization Of 304l Stainless Steel By Means Of Minimum Input Energy On The Selective Laser Melting Platform, Ben Brown Jan 2014

Characterization Of 304l Stainless Steel By Means Of Minimum Input Energy On The Selective Laser Melting Platform, Ben Brown

Masters Theses

"Developing parameter sets for new materials on the Selective Laser Melting (SLM) platform has traditionally been done through the use of single line processing windows and a basic design of experiments (DOE) which would include varying machine parameters to maximize density. This study expands the traditional method by determining the main effects statistically for density, allowing for a more in depth analysis wherein the experimental results are statistically correlated to the variable machine parameters used. With this analysis, parameter optimization with respect to achieving near full density, while also considering build rates, can be performed. New parameters for 304L stainless …


Energy Efficient Scheduling And Allocation Of Tasks In Sensor Cloud, Rashmi Dalvi Jan 2014

Energy Efficient Scheduling And Allocation Of Tasks In Sensor Cloud, Rashmi Dalvi

Masters Theses

"Wireless Sensor Network (WSN) is a class of ad hoc networks that has capability of self-organizing, in-network data processing, and unattended environment monitoring. Sensor-cloud is a cloud of heterogeneous WSNs. It is attractive as it can change the computation paradigm of wireless sensor networks. In Sensor-Cloud, to gain profit from underutilized WSNs, multiple WSN owners collaborate to provide a cloud service. Sensor Cloud users can simply rent the sensing services which eliminates the cost of ownership, enabling the usage of large scale sensor networks become affordable. The nature of Sensor-Cloud enables resource sharing and allows virtual sensors to be scaled …


A Modified Initiation And Cut Profile Study Of The 10500 Grain Per Foot Linear Shaped Charge, Matthew Ortel Jan 2014

A Modified Initiation And Cut Profile Study Of The 10500 Grain Per Foot Linear Shaped Charge, Matthew Ortel

Masters Theses

"A 10,500 grain per foot (gr/ft.) linear shaped charge (LSC) was developed to cut targets that were too thick for smaller LSC. The manufacturer observed shallower penetration from the 10,500 gr/ft. LSC than was expected. This prompted investigations to uncover the cause of the perceived reduced performance.

A study performed at the Missouri University of Science and Technology changed the initiation method of the 10,500 gr/ft. charge to increase the cut performance of the charge. A modified two point, single end initiation method was devised and tested. This initiation method was termed "dual initiation" and focused on creating a planar …


Shear-Wave Splitting And Mantle Deformation Beneath The Western Tibetan Plateau, Melissa Ann Ray Jan 2014

Shear-Wave Splitting And Mantle Deformation Beneath The Western Tibetan Plateau, Melissa Ann Ray

Masters Theses

"The Tibetan Plateau has been an enigma to the scientific community since scientists first began to focus their attention on the area. Numerous studies over the decades were conducted to address how the plateau formed, mostly in the central and eastern portions of the Tibetan Plateau. Many questions still remain regarding the western Tibetan Plateau, and this study will add constraints to the mechanisms which regulated the formation of the plateau.

Data was acquired from over 13,000 measurements from 172 stations covering the western region of the plateau encompassing the Qiangtang Terrane, the Lhasa Terrane, and the Himalayan Orogenic Zone. …


An Iterative Algorithm For Variational Data Assimilation Problems, Xin Shen Jan 2014

An Iterative Algorithm For Variational Data Assimilation Problems, Xin Shen

Masters Theses

"Data assimilation is a very powerful and efficient tool to use collected raw data for improving model prediction in numerical weather forecasting, hydrology, and many other areas of geosciences. In this thesis, an iterative algorithm [23] of variational data assimilation with finite element method is utilized to study different models. One motivation for this fundamental mathematical study is to provide a potential tool for simulation of CO2 sequestration by extending it to more realistic and sophisticated models in the future. The basic idea of variational data assimilation is to utilize the framework of optimal control problems. We apply the …


The Use Of Statistics And Its Analysis In Resolving Transportation Related Problems, Venkat Sravan Kothapalli Jan 2014

The Use Of Statistics And Its Analysis In Resolving Transportation Related Problems, Venkat Sravan Kothapalli

Masters Theses

"Statistical methods are traditionally used to summarize or describe a collection of data. This can be termed as descriptive statistics. This research focuses on application of certain statistical approaches, tools to solve transportation related problems. This research focuses on usage of statistical analysis in determine some of the significant factors and assumptions which should be taken into consideration while developing safety and maintenance related measures by transportation agencies. This research mainly focuses on; testing null hypothesis and frequency analysis. The research therefore is presented in two different case studies: 1) Statistical analysis of the work zone crash historical raw data …


On Temporal And Frequency Responses Of Smartphone Accelerometers For Explosives Detection, Srinivas Chakravarthi Thandu Jan 2014

On Temporal And Frequency Responses Of Smartphone Accelerometers For Explosives Detection, Srinivas Chakravarthi Thandu

Masters Theses

"The increasing frequency of explosive disasters throughout the world in recent years have created a clear need for the systems to monitor for them continuously for better detection and to improve the post disaster rescue operations. Dedicated sensors deployed in the public places and their associated networks to monitor such explosive events are still inadequate and must be complemented for making the detection more pervasive and effective. Modern smart phones are a rich source of sensing because of the fact that they are equipped with wide range of sensors making these devices an appealing platform for pervasive computing applications. The …


Influence Of Erosional Unloading On The State Of Stress For Low Amplitude Single-Layer Buckle Folds - Implications For Tensile Fracture Occurrence, Mengke Li Jan 2014

Influence Of Erosional Unloading On The State Of Stress For Low Amplitude Single-Layer Buckle Folds - Implications For Tensile Fracture Occurrence, Mengke Li

Masters Theses

"The existence of fractures associated to buckle folds is related to the strain distribution of the fold. The erosional unloading process can amplify the remnant strain in the folded layer. Two-dimensional plane strain Finite Element Analysis (FEA) is used to investigate the influence of the erosional unloading step on both the evolution of the state of stress and the associated failure patterns in low amplitude buckle folds. Sensitivity analyses on different input parameters, including viscosity, shortening ratio, and overburden pressure, are performed. Based on the simulation results, tensile stress can be initiated both in the crest and in the limb …


Polyurethane Foam Infill For Fiber Reinforced Polymer (Frp) Bridge Deck Panels: An Evaluation Of Core Alternatives Using Small Scale Experimental Testing, Matthew Scott Hopkins Jan 2014

Polyurethane Foam Infill For Fiber Reinforced Polymer (Frp) Bridge Deck Panels: An Evaluation Of Core Alternatives Using Small Scale Experimental Testing, Matthew Scott Hopkins

Masters Theses

"Fiber reinforced polymer (FRP) decking is a concept that has been explored in recent decades as one solution to the performance issues of conventional concrete bridge decking. Many sandwich panel designs made of glass reinforced polyester or vinyl ester resin have been well developed, and manufactured using filament winding, hand lay-up, and extrusion methods. The major benefits of these panels was their light weight, corrosion resistance, fatigue performance, and potential for rapid field assembly. However, high initial costs coupled with small state budgets have kept them from main stream adoption. A viable alternative, is a foam/reinforced foam core sandwich panel …


Top-K With Diversity-M Data Retrieval In Wireless Sensor Networks, Kiran Kumar Puram Jan 2014

Top-K With Diversity-M Data Retrieval In Wireless Sensor Networks, Kiran Kumar Puram

Masters Theses

"Wireless Sensor Network is a network of a few to several thousand sensors deployed over an area to sense data and report that data back to the base station. There are many applications of wireless sensor networks including environment monitoring, wildlife tracking, troop tracking etc. The deployed sensors have many constraints like limited battery, limited memory and very little processing capacity. These constraints show direct effect on the network life time.

In many applications of Wireless Sensor Networks, such as monitoring chemical leak, the user is not interested in all the data points from the entire region, but may want …


Uterine Cervical Cancer Histology Image Feature Extraction And Classification, Koyel Banerjee Jan 2014

Uterine Cervical Cancer Histology Image Feature Extraction And Classification, Koyel Banerjee

Masters Theses

"The current study presents the investigation and development of image processing, computational intelligence, fuzzy logic, and statistical techniques for different types of data fusion for a varied range of applications. Raw data, decision level and feature level fusion techniques are explored for detection of pre Cervical cancer (CIN) grades from digital histology images of the cervical epithelium tissues.

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. The approach included medial axis determination, vertical segment partitioning as medial axis …


Performance Evaluation Of Coaxial Horizontal Axis Hydrokinetic Turbines System, Abdulaziz M. Abutunis Jan 2014

Performance Evaluation Of Coaxial Horizontal Axis Hydrokinetic Turbines System, Abdulaziz M. Abutunis

Masters Theses

"Hydrokinetic energy technologies are emerging as a viable solution for renewable power generation. Unlike conventional hydropower turbines, hydrokinetic turbines are environmentally friendly; they operate at zero-head, and do not need dams to preserve the water. Unfortunately, they have a low efficiency which makes their design a challenging task. This work was focused on the hydrodynamic performance of horizontal axis hydrokinetic turbines (HAHkTs) under different turbine arrangements and flow conditions.

It was undertaken in an effort to improve the efficiency of small HAHkTs that harness a river's kinetic energy. Four sets of experiments were performed in a water tunnel to investigate …


Hidden Markov Model With Information Criteria Clustering And Extreme Learning Machine Regression For Wind Forecasting, Dao Lam, Shuhui Li, Donald C. Wunsch Jan 2014

Hidden Markov Model With Information Criteria Clustering And Extreme Learning Machine Regression For Wind Forecasting, Dao Lam, Shuhui Li, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a procedural pipeline for wind forecasting based on clustering and regression. First, the data are clustered into groups sharing similar dynamic properties. Then, data in the same cluster are used to train the neural network that predicts wind speed. For clustering, a hidden Markov model (HMM) and the modified Bayesian information criteria (BIC) are incorporated in a new method of clustering time series data. to forecast wind, a new method for wind time series data forecasting is developed based on the extreme learning machine (ELM). the clustering results improve the accuracy of the proposed method of wind …


Emi Investigation And Modeling Of A Flat Panel Display, Satyajeet Shinde Jan 2014

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 …


Nonlinear Development And Secondary Instability Of Traveling Crossflow Vortices, Fei Li, Meelan M. Choudhari, Lian Duan, Chau-Lyan Chang Jan 2014

Nonlinear Development And Secondary Instability Of Traveling Crossflow Vortices, Fei Li, Meelan M. Choudhari, Lian Duan, Chau-Lyan Chang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Building upon the prior research targeting the laminar breakdown mechanisms associated with stationary crossflow instability over a swept-wing configuration, this paper investigates the secondary instability of traveling crossflow modes as an alternate scenario for transition. For the parameter range investigated herein, this alternate scenario is shown to be viable unless the initial amplitudes of the traveling crossflow instability are lower than those of the stationary modes by considerably more than one order of magnitude. The linear growth predictions based on the secondary instability theory are found to agree well with both parabolized stability equations and direct numerical simulation, and the …