Digital Commons Network^™

In Vivo Evaluation Of Microfibrous Bioactive Borate Glasses For Use In Wound Healing, Yinan Lin

Masters Theses

"This project consisted of two parts focused on in vivo evaluation of microfibrous bioactive borate glasses for use in wound healing. Part one of the project involved subcutaneous implantation of two types of borate glass microfibers and 45S5 glass micro fibers in the dorsum of rats and histologically evaluating the soft tissues at the implant sites at 2 to 4 weeks post surgery. The primary objective was to assess the angiogenic response to the implanted materials. The 13-93B3 and 13-93B3Cu glass microfibers were found to significantly increase the microvascular density in soft tissue, an outcome that suggests these simple and …

Hardened Mechanical Properties And Durability Performance Of Specialized Concretes, Kyle Richard Holman

Masters Theses

"Concrete is one of the most produced and utilized materials in the world. Due to the labor intensive and time consuming nature of concrete construction, new and innovative concrete mixes are being explored. Self-consolidating concrete (SCC) is one such method of improving the overall cost and time efficiency of concrete production. SCC is a highly flowable form of concrete. This characteristic drastically reduces the amount of labor and time needed to place the concrete. The highly flowable nature also allows for much easier placement in applications of highly congested reinforcement.

Another rising concern in today's construction industry is environmental responsibility. …

Enrollment And Academic Outcomes Of English Language Learners In Pre-K To Grade 3 In The Boston Public Schools, Sy2009: Data Points For A Discussion At Wheelock College, Miren Uriarte, Faye Karp

Gastón Institute Publications

This brief report focuses on the enrollment, characteristics and academic outcomes of English Language Learners in Pre-Kindergarten to Grade 3 in comparison with those of English proficient students and all students at these grade levels. The purpose of the report is to generate discussion about ways in which the learning needs of these students can best be met. As proposed, the report consists primarily of data tables and annotations organized around five sets of questions.

Development Of A Shared Earth Model To Investigate Potential For Carbon Dioxide Sequestration In The Springfield Area, Mo, Imowo Celestine Akpan

Masters Theses

"Carbon dioxide (C0₂) sequestration has been extensively implemented and explored predominantly in depleted oil reservoirs and deep saline aquifers where the C0₂ is stored under supercritical conditions. A lesser explored option with great potential is based on injection into shallow reservoirs where the C0₂ may not always be in its denser supercritical state. The research evaluates the potential for injecting C0₂ into saline aquifers at depths of ~550-650 meters and formation temperatures of -22⁰C.

To evaluate injectivity and cap rock integrity, reservoir and geomechanical simulations need to be conducted separately and subsequently coupled. A Shared Earth Model is developed utilizing …

Wavelet Based Contrast Limited Histogram Equalization For Contrast Enhancement Of Digital Mammography, Ashish Vighnahar Avachat

Masters Theses

"Mammography has been the most efficient tool for screening of microcalcification and cancer tissues; however, the raw images produced by mammography systems are usually of poor contrast. In order to use these raw images for early diagnosis; their contrast, sharpness and noise need to be enhanced. Among these important enhancement parameters contrast enhancement is critical. A novel algorithm is introduced which blends wavelet transforms with Contrast Limited Adaptive Histogram Equalization (CLAHE) for contrast enhancement. In this algorithm, the input image is decomposed to its low frequency and high frequency components in wavelet domain. Decomposed coefficients from different bands are then …

A Three-Dimensional Transient Simulation Of An Electrochemical Magnetohydrodynamics Cell With Micro And Millielectrode: A Unified Reconciliation Of Theory And Experiment, Cajon Gonzales

Masters Theses

"Even though electrochemically induced magnetohydrodynamic (MHD) convection is a straightforward inexpensive method for moving fluids in confined spaces as for example during electrodeposition, stripping voltammetry, or in microfluidics, efficient quantitative models only recently have begun to appear. This is traced to complex mathematics that have prevented development of analytical expressions, e.g., for mass-transfer limited currents in analogy to the well-known Levich equation for the rotating electrode. Thus, related literature expressions remain mainly phenomenological concerning particular cell geometries or applications. Here, using such reports as points of departure, we validate a computationally rigorous description of the magnetoelectrochemical problem and define the …

Impact Of Interruptions In White Collar Working Environment, Zafar Akhil Khan

Masters Theses

"An interruption is a randomly occurring, discrete event that breaks continuity of cognitive focuses on a primary task and typically requires immediate attention and insists on action. "White collar interruptions" are those that affect knowledge workers in professional, managerial, or administrative positions. Interruptions are often a common occurrence in the white collar workplace.

The aim of this thesis is to investigate the effect of timing of an interruption on the overall performance of white collar workers. This study also analyzes the interruption sources (i.e. externally and internally generated) along with effect of different types of interruptions on both demanding and …

Prototyping And Testing Of Solar Hybrid Pv-T Panels, Joel Aaron Lamson

Masters Theses

"The combination of photovoltaic and solar thermal (PV-t) systems has been proven to provide greater efficiency than their stand-alone counterparts. Previous studies on hybrid assemblies have found favorable results supporting the combination of both systems. The research presented here builds on the work competed here at Missouri University of Science and Technology (Missouri S&T) yielding favorable results of increased efficiencies as compared to stand-alone systems. The main difference between this experiment and previous research at Missouri S&T is that the hybrid PV-t is unglazed. The effect of an unglazed panel is shown to reduce the thermal output of the PV-t …

Cerium-Based Conversion Coatings On Cast Aluminum 380 And 413 Alloys, Ci Lin

Masters Theses

"This investigation focused on the deposition and characterization of cerium-based conversion coatings (CeCCs) on cast aluminum alloys. Previous research has shown that CeCCs are viable alternatives to chromate conversion on high strength alloys such as 2024-T3 and 7075-T6. For the casting alloys such as 380 and 413, the presence of Si affects the composition and stability of the native oxide, which means that pretreatment plays an important role for the coating deposition. This thesis consists of two papers that describe the results of the study.

The first paper reports the effect of the final rinsing temperature before coating deposition on …

Spiking Neural Networks Encoding And Decoding Algorithms For Time Series Estimation And System Identification, Sinchan Roychowdhury

Masters Theses

"Artificial Neural networks (ANNs) have increasingly been applied to different system identification, pattern recognition and function approximation problems. The predominantly used neural network architectures are the feedforward and feedback networks. Multilayer perceptrons and radial basis function networks are among the most commonly used feed-forward architecture neural networks and the Elman and Jordan networks are the most widely used recurrent neural networks. These networks are also called as second generation ANNs.

This thesis focuses on the third generation ANNs which are biologically inspired and operate on the same principles as the living neurons. These are also known as biologically inspired artificial …

In Planta Solid Phase Sampling Devices Used In Delineating Groundwater Contaminant Plumes, Mikhil Kishore Shetty

Masters Theses

"The widespread and indiscriminate use of chlorinated volatile organic compounds as cleaning agents at dry - cleaning facilities, as metal degreasers and solvents in extraction and removal operations has been well documented in the past resulting in releases, while contaminating soil and groundwater. Current techniques to assess chlorinated solvents such as tetrachloroethylene (PCE) and trichloroethylene (TCE) in the subsurface have been time and cost intensive and more importantly invasive to the surrounding environment. New methods use trees as sources of information to access contaminant plume size and plume delineation. The major goal of these research studies has been to save …

Making Popular Constitutionalism Work, Thomas G. Donnelly

Law Faculty Publications

Popular constitutionalism defies easy definition. Its leading theorists fail to offer a common reading of constitutional history, a common methodology, or even a common set of remedies. Given these diverse approaches, it is little wonder that one recurring complaint among popular constitutionalism's critics is that the theory itself is incoherent. This criticism is overstated. Even as there are various strands of popular constitutionalism, its leading theorists do share one key attribute, a populist sensibility-a common belief that the American people (and their elected representatives) should play an ongoing role in shaping contemporary constitutional meaning. The question remains how best to …

Effect Of Side Edge Distance And Concrete Materials On Corrosion In Precast Prestressed Concrete Panels, Dayi Zhang

Masters Theses

"This study involved the spalling problem found in some partial-depth precast prestressed bridge decks in the state of Missouri. Recently, panels of several bridges have exhibited corrosion of the prestressing steel tendons causing concrete spalling at the edges of panels. Some of the exposed tendons are corroded to the point of rupture. The effect of factors, namely concrete side edge distance and concrete material type, on steel corrosion in chloride-contaminated reinforced concrete was investigated in this study. Wet-dry cycle tests and accelerated corrosion tests were carried out on sixty-three specimens designed with three different side edge distances and three different …

Locating Current Paths Via Time Synchronized Measurements In A Multiphase Dcdc Buck Converter And A High Frequency Analytical Model For The Common-Mode Impedance Of A Ferrite Choke, Peng Shao

Masters Theses

"In the first section, it introduces a novel method to localize current from multiple sources. The identification of return current paths is often a key element in understanding the root cause of a product's radiated emissions. In a complex system, multiple sources can contribute to the current at the same location and frequency. The source of the current can be identified by correlating the current to different sources. However, the multiphase buck converter phases do not switch at the same time. Thus, synchronizing to a specific phase makes it possible to determine how the current from a specific phase spreads …

Determination Of Linear Attenuation Coefficients Of Chemically Bonded Phosphate Ceramics, Jason Joseph Pleitt

Masters Theses

"Chemically Bonded Phosphate Ceramics (CBPCs) is a composite based material formed in a manner similar to cements. CBPCs have shown to be a good structural material with excellent thermal resistance properties. They have also been shown to have potential as a radiation shield. By incorporating various powders into the ceramic the improvement in its radiation shielding properties are examined. The method for obtaining the linear attenuation coefficients for CBPCs as well as MCNP simulated results for gamma and neutrons are presented"--Abstract, page iv.

Experimental Investigation Of Rf Fading Channels And Receiver Detection, Saurav Kumar Subedi

Masters Theses

"This thesis includes experimental investigation of Multiple Input Multiple Output (MIMO) Radio Frequency (RF) fading channels and detection of superregenerative receivers. Details of experiment design and hardware implementation, data acquisition and analysis, and results for both studies are chronicled into two papers. The first paper investigates the validity of the discrete time triply selective fading channel model for fixed mobile-to-mobile MIMO channels. A 2x2 MIMO-OFDM testbed using the Altera Stratix III EP3SL150F field programmable gate array (FPGA) DSP development kit is used for acquiring experimental data. Subsequent offline signal processing and analysis are done in MATLAB. The Channel Impulse Response …

Effect Of Lipid Composition On The Physical Properties Of Liposomes: A Light Scattering Study, Rajiv Kumar Yandrapati

Masters Theses

"The aim of this study was to investigate the effect of lipid composition on the physical properties of liposomes. Eight different types of liposomes were prepared for this study. Liposomes consisting of phosphatidylcholine (PC) and cholesterol were prepared in three different compositions 80/20, 50/50 and 20/80 respectively. Similarly liposomes consisting of PC and negatively charged phosphatidylserine (PS) were also prepared in three different compositions 80/20, 50/50 and 20/80 respectively. Two liposomes with the compositions 2:2:1:1 (cholesterol:PC:phosphatidylglycerol (PG): phosphatidylethanolamine (PE) ) which resembles the myelin membrane and 10:5:7.5:16 (PC:PE:PS:cholesterol) which mimics rat's neural membranes were also prepared. The liposomes were prepared …

Unified Knowledge Model For Stability Analysis In Cyber Physical Systems, Tamal Paul

Masters Theses

"The amalgamation and coordination between computational processes and physical components represent the very basis of cyber-physical systems. A diverse range of CPS challenges had been addressed through numerous workshops and conferences over the past decade. Finding a common semantic among these diverse components which promotes system synthesis, verification and monitoring is a significant challenge in the cyber-physical research domain. Computational correctness, network timing and frequency response are system aspects that conspire to impede design, verification and monitoring. The objective of cyber-physical research is to unify these diverse aspects by developing common semantics that span each aspect of a CPS. The …

Vehicle Path Verification Using Wireless Sensor Networks, Gerry W. Howser

Masters Theses

"Path Verification is a problem where a verifier would like to determine how closely a vehicle actually traversed a path that it claims to have traversed. This problem has critical significances in terms of vehicle mobility. Mobile nodes can be patrols officers or cab drivers, while respective verifiers can be police dispatchers or cab operators. In this paper, we design a sensor network assisted technique for vehicle path verification. In our design, a number of static wireless sensors placed in road segments will serve as witnesses and certify vehicles as they move. Post movement, these witness certificates will be utilized …

Optical Coherence Tomography For Biomedical Imaging, Edward Henry Pienkowski

Masters Theses

"Two projects are presented in this thesis; 1) a hollow core, concentrically symmetric beam splitting Michelson interferometric probe for optical coherence tomography and 2) the imaging of bioactive ceramic scaffolds using swept source optical coherence tomography. The key component of the interferometer is a compact, small diameter probe composed of a collimating lens, hollow core beam splitting tube, and a focusing lens intended to be used for endoscopic imaging. The beam splitting tube was created by sputter coating the distal endface of a finely polished thick wall capillary tube with a highly reflective gold layer. Part of the light travels …

A Digitally Implemented Practical Photovoltaic Simulator With A Double Current Mode Controller, Jie Ang Zhao

Masters Theses

"This thesis presents a microcontroller- and DC-DC converter-based photovoltaic (PV) simulator which emulates the output characteristic of a PV module. The current-voltage (IV) characteristic of a PV module is implemented as a look-up-table that generates an output reference current based on a measured output voltage. The control mechanism is based on a double current mode controller that consists of a predictive current mode controller and a proportional-integral (PI) controller arranged in an inner loop and outer loop configuration. The PI controller is designed based on classical phase margin and gain margin criteria to ensure system stability. The performance of the …

Hydraulic Fracturing Experiments To Investigate Circulation Losses, Maximiliano Liberman

Masters Theses

"In recent years the oil and gas industry has been drilling more challenging wells due to long deviated wells, drilling through already depleted reservoirs, sub salt wells and increasing water depth. A major challenge these wells create is to prevent fluid loss into the formation and wellbore breakouts by having accurately determined the mud weight operational window. In addition to accurately determine the fracture gradient, additives in the drilling fluid have been used to enhance the fracture gradient in an industry process named wellbore strengthening. In order to study the phenomenon of fracture gradient alteration, a hydraulic fracturing apparatus was …

Thermal Modeling And Analysis Of Polymer Electrolyte Membrane Open Cathode Fuel Cells, Blanca Ollero Loranca

Masters Theses

"In the past decade renewable energies have increasingly become a commodity in everyday life. Because of their high power densities and their application versatility, fuel cells have stood out among other sources of renewable energy. In order to improve this technology as the needs for it increases, thermal modeling is an essential step. Researchers in the past have investigated the effect that temperature has on fuel cells. However, not much work has been done on the thermal dynamics of these devices and no one, to the authors knowledge, has studied the speed of response in thermal changes as a function …

Control Oriented Thermal Modeling Of Lithium Ion Batteries, Derek Brown

Masters Theses

"Lithium ion batteries have been widely used in consumer electronics and are beginning to move to the forefront of the automotive and power grid industries. Lithium ion batteries are desirable in these applications because they are high energy density and high specific energy cells, while remaining inexpensive and lightweight. Safety is a concern in every consumer application; therefore, in order for lithium ion battery use to continue growing, advances in battery management systems are needed. Thermal management of lithium ion batteries is currently a critical issue. Applications are becoming more dependent on active liquid thermal management systems. The development of …

Abel Dynamic Equations Of The First And Second Kind, Sabrina Heike Streipert

Masters Theses

"In this work, we study Abel dynamic equations of the first and the second kind. After a brief introduction to time scales, we introduce the Abel differential equations of the first and the second kind, as well as the canonical Abel form in the continuous case. Using the existing information, we derive novel results for time scales. We provide formulas for the Abel dynamic equations of the second kind and present a solution method. We furthermore achieve a special class of Abel equations of the first kind and discuss the canonical Abel equation. We get relations between common dynamic equations …

A Study Of The Integration Of An Inlet Noise Radiation Code With The Aircraft Noise Prediction Program, Devin Kyle Boyle

Masters Theses

"A numerical method has been developed in order to study the effect of turbofan inlet acoustic treatment on the resulting cumulative noise heard by observers on the ground. The approach to creating the tool was to combine the capabilities of the NASA-developed Aircraft Noise Prediction Program (ANOPP) with the fan noise propagation and radiation code developed at Missouri University of Science and Technology. ANOPP can be used to predict the noise metrics resulting from a typical commercial aircraft with turbofan engines on several different flight profiles, including takeoff, approach/landing and a steady (constant altitude/airspeed) flyover. These capabilities are valuable for …

Electromagnetic Compatibility Of Integrated Circuit Clock Design, Vijay Kanagachalam

Masters Theses

"With advancements in technology, transistor sizes are shrinking resulting in reduced power supply voltage and thereby reduced noise margin which makes the devices susceptible to electromagnetic noises. The trend of integrating more circuits on a single die at ever growing operating frequency increases interference among circuits and with the outside world. In order to make circuits electromagnetically compatible, it is essential to reduce emissions from the circuit and understand the causes of failure due to interference of noise from other sources coupling into the circuit so that a robust design can be created.

Two topics are explored in this thesis. …

Investigation Of Geosteering In Non-Trivial Geological Settings, Anuroop Pandey

Masters Theses

"The well placement technology has advanced to a stage where we can explore small tolerance targets such as thin reservoirs. Well placement with geosteering, which is the real time adjustment of the well path based on the geological responses to place and maintain the well within the best part of the reservoir, is the technology that has made this progress possible. Geosteering however can get very complex with the increasing heterogeneities of the formations and there is no fixed methodology to devise a steering strategy in such complex geological settings. To accommodate this challenge, we investigated three methods to verify …

Surfactant Enhanced Oil Recovery By Wettability Alteration In Sandstone Reservoirs, Omar Elmofty

Masters Theses

"Recovering more oil from existing oil reservoirs using enhanced oil recovery methods holds the key for meeting future energy demands. Even though wettability is a cornerstone in oil recovery, few studies have focused on increasing oil recovery in sandstone reservoirs through wettability alteration. The objective of this thesis is to prove that altering the wettability of a sandstone rock to preferentially water-wet condition will reduce the remaining oil saturation and thus increase the percentage of recovered oil.

Two commercial surfactants were selected after studying both the phase behavior and the interfacial properties of 30 surfactants with oil and 1.00% sodium …

Investigating The Effects Of Internally Trapped Residuals On The Performance Of A Homogeneous Charge Compression Ignition (Hcci) Engine, Aaron David Attebery

Masters Theses

"Homogeneous charge compression ignition (HCCI) combustion introduces great opportunity for decreased emissions along with greater engine efficiencies. Implementing an innovative combustion mode such as HCCI presents a great challenge for the engine research community. One such challenge is controlling the innate cyclic variability from this chemical kinetics controlled auto-ignition event when transitioning to or from a SI operating mode. This work includes the study of cycle-to-cycle dynamics that occur within the partial burn regime of an HCCI engine as it approaches the misfire limit. Within this regime there are many successive incomplete combustion events that will impact the next cycle …