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2012

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Identification Of Starry Milia-Like Cysts In Seborrheic Keratoses And Malignant Melanomas Using Image Processing Techniques, Viswanaath Subramanian Jan 2012

Identification Of Starry Milia-Like Cysts In Seborrheic Keratoses And Malignant Melanomas Using Image Processing Techniques, Viswanaath Subramanian

Masters Theses

"Seborrheic keratoses are the most common benign tumors found in older individuals. Seborrheic keratoses are normally benign in nature, but sometimes in a large lesion area of seborrheic keratoses, secondary tumors, or squamous cell carcinoma in situ or malignant melanoma may occur. It has been found that seborrheic keratoses have a few features that distinguish them from melanomas. Milia-like cysts, comedo-like openings and network-like structures are the most prominent features found in seborrheic keratoses. Comedo-like openings are pigmented structures and are mostly oval yellowish, brown or black in appearance. They can also be observed in melanocytic lesions and melanomas. Milia-like …


The Effect Of Geographical Scale Of Sampling On Dna Barcoding., Johannes Bergsten, David T. Bilton, Tomochika Fujisawa, Miranda Elliott, Michael T. Monaghan, Michael Balke, Lars Hendrich, Joja Geijer, Jan Herrmann, Garth N. Foster, Ignacio Ribera, Anders N. Nilsson, Timothy G. Barraclough, Alfried P. Vogler Jan 2012

The Effect Of Geographical Scale Of Sampling On Dna Barcoding., Johannes Bergsten, David T. Bilton, Tomochika Fujisawa, Miranda Elliott, Michael T. Monaghan, Michael Balke, Lars Hendrich, Joja Geijer, Jan Herrmann, Garth N. Foster, Ignacio Ribera, Anders N. Nilsson, Timothy G. Barraclough, Alfried P. Vogler

School of Biological and Marine Sciences

Eight years after DNA barcoding was formally proposed on a large scale, CO1 sequences are rapidly accumulating from around the world. While studies to date have mostly targeted local or regional species assemblages, the recent launch of the global iBOL project (International Barcode of Life), highlights the need to understand the effects of geographical scale on Barcoding's goals. Sampling has been central in the debate on DNA Barcoding, but the effect of the geographical scale of sampling has not yet been thoroughly and explicitly tested with empirical data. Here, we present a CO1 data set of aquatic predaceous diving beetles …


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 Jan 2012

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 Jan 2012

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 Jan 2012

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 Jan 2012

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 Jan 2012

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 Jan 2012

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 Jan 2012

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 Jan 2012

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 …


How Should Plastic-Packaging Companies Apply Artificial Proofs And Topics Of Invention To Communicate Sustainability? : A Heuristic Developed On The Basis Of Rhetorical Analysis, Shristy Bashyal Jan 2012

How Should Plastic-Packaging Companies Apply Artificial Proofs And Topics Of Invention To Communicate Sustainability? : A Heuristic Developed On The Basis Of Rhetorical Analysis, Shristy Bashyal

Masters Theses

"This study examines how the ten plastic-packaging companies use artificial proofs and topics of invention to communicate sustainability-related information. The objective of this study was to answer the following research questions:

(i) Do plastic-packaging companies define sustainability on their website?

(ii) What are the strengths and weaknesses of the arguments in these companies' sustainability-related communications?

(iii) What invention strategies should technical marketing communicators use to communicate company's sustainable practices?

To answer these questions, I analyzed the sustainability-related documents available on the websites of the ten companies. On the basis of this analysis, I developed an invention heuristic that can be …


Enhancing The Aerodynamic Performance Of Stepped Airfoils, Ranganadhan Voona Jan 2012

Enhancing The Aerodynamic Performance Of Stepped Airfoils, Ranganadhan Voona

Masters Theses

"The main objective of this research was to investigate the lift and drag characteristics of a stepped airfoil with backward facing steps; apply active flow control technique to enhance the aerodynamic performance of stepped airfoils and examine the possibility of using such airfoils on Unmanned Aerial Vehicles (UAV's). A step was introduced at mid-chord, with a depth of 50% of the airfoil thickness at mid-chord position extending till the trailing edge of a NACA 4415 airfoil. Computational studies were conducted with the use of passive flow control constituting the activation of step and active flow control with the use of …


Investigation Of The Effects Of Shrinkage, Creep, And Abrasion On Self-Consolidating Concrete And High Volume Fly Ash Concrete For Use In Transportation Related Infrastructure, Brian Timothy Tucker Jan 2012

Investigation Of The Effects Of Shrinkage, Creep, And Abrasion On Self-Consolidating Concrete And High Volume Fly Ash Concrete For Use In Transportation Related Infrastructure, Brian Timothy Tucker

Masters Theses

"Concrete specimens were fabricated for shrinkage, creep, and abrasion resistance testing. Variations of self-consolidating concrete (SCC), high volume fly ash concrete (HVFA), and conventional concrete were studied. The results were compared to previous similar testing programs and used to determine the adequacy of the materials for use in practice. These two concrete variations offer significant benefits when used as replacements to conventional concrete. Because of the respective properties of both types of concrete, both economic and environmental benefits are achieved with the use of both. The lower labor costs of SCC and the lower material cost of HVFA lead to …


Sapphire Fiber Numerical Aperture Measurement And Sensor Fabrication, Xia Fang Jan 2012

Sapphire Fiber Numerical Aperture Measurement And Sensor Fabrication, Xia Fang

Masters Theses

"A sapphire fiber is made of single crystal aluminum oxide with hexagonal crystal structure. It is attractive for high temperature application for its chemical resistance and high melting point of 2053⁰C. It is good for infrared transmission with a small attenuation of 0.13dB per meter at the wavelength of 2.94µm, and it can also deliver very high optical energy. However, a typical sapphire fiber has a rough surface and a nonperfect crystalline structure. Also, a sapphire fiber cannot be grown in a core-clad structure. The un-cladded waveguide imposes a number of undesirable characteristics on sensing applications, e.g., unpredictable light loss …


Hydraulic Fracturing Experiments To Investigate Circulation Losses, Maximiliano Liberman Jan 2012

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 Jan 2012

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 Jan 2012

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 …


A Study Of The Integration Of An Inlet Noise Radiation Code With The Aircraft Noise Prediction Program, Devin Kyle Boyle Jan 2012

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 …


Evaluation Of The Reagan And Lamotte Sandstones In Southwestern Missouri For Carbon Dioxide Sequestration, Todd Jeffrey Miller Jan 2012

Evaluation Of The Reagan And Lamotte Sandstones In Southwestern Missouri For Carbon Dioxide Sequestration, Todd Jeffrey Miller

Masters Theses

"Carbon dioxide sequestration has been proposed as a way to reduce anthropogenic carbon dioxide emissions. Several characteristics are required in order for a geologic formation to be suitable for sequestration. There must be an impermeable confining layer to restrain CO₂ migration toward the surface, the porosity and permeability must be high enough to allow for long term injection and substantial storage capacity, and the formation must be strong enough for long term injection to occur without inducing fractures. In this work, The Reagan and Lamotte Sandstones near Springfield, Missouri were evaluated for the potential for carbon dioxide sequestration. The Derby-Doe …


Surfactant Enhanced Oil Recovery By Wettability Alteration In Sandstone Reservoirs, Omar Elmofty Jan 2012

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 …


Geomechanical Characterization Of Reservoir & Cap Rocks For Co₂ Sequestration, Sudarshan Govindarajan Jan 2012

Geomechanical Characterization Of Reservoir & Cap Rocks For Co₂ Sequestration, Sudarshan Govindarajan

Masters Theses

"Geological sequestration of CO₂ has been identified as one method to reduce global emissions of CO₂ and achieve lower levels of CO₂ concentrations in the atmosphere. Geological formations have to be assessed in terms of their capacity, sealing capabilities and economic feasibility before CO₂ sequestration can commence. Potential leakage of injected CO₂ from the reservoir formation could occur due to natural or injection induced faults or fractures in the reservoir or sealing formations. As part of a potential leakage investigation a geomechanical characterization which refers to the assessment of the in-situ stress conditions, rock strength and stiffness properties of the …


Process Simulation And Inclusion Characterization In Stainless Steel Ingot Casting, Jun Ge Jan 2012

Process Simulation And Inclusion Characterization In Stainless Steel Ingot Casting, Jun Ge

Masters Theses

"For the ingot casting process, fluid flow of steel plays an important role in quality control and industrial operations. Using CFD software (FLUENT), this study overviews the fluid flow pattern in the bottom-teeming ingot filling process with three different swirl-modified upgate designs. Turbulent flow and mass transfer are considered main factors in controlling the process. The motion of the slag phase was also considered. In addition to the modeling studies, inclusions in stainless steel poured into ingots with a traditional and a swirl-modified upgate system were investigated using an optical microscope, SEM-EDS and ASPEX automated feature analysis technology. The main …


Depositional And Tectonic Controls On Architecture Of The Carbonate Platform Of Upper Paleocene Khalifah Formation, Sirte Basin, Central Libya, Salah Abdurzak Shaniba Jan 2012

Depositional And Tectonic Controls On Architecture Of The Carbonate Platform Of Upper Paleocene Khalifah Formation, Sirte Basin, Central Libya, Salah Abdurzak Shaniba

Masters Theses

"The Paleocene strata in Sirte Basin, Libya, contain major oil and gas accumulations in a variety of lithofacies of reef and bioherm carbonate depositional environments. The Upper Paleocene Khalifah Formation, which is one of the main reservoirs containing about 30% of the oil reserves of the Sirte Basin, is composed of shallowing-upward and carbonate platform deposits and is capped by open marine shale deposits formed during a marine transgression. Well and seismic data are used to interpret the depositional environments and identify upward shallowing and deepening trends in the formation. In the study area, Mabruk oil field in northwestern Sirte …


Self-Consolidating Concrete For Infrastructure Elements Shear Characteristics, Eric B. Sells Jan 2012

Self-Consolidating Concrete For Infrastructure Elements Shear Characteristics, Eric B. Sells

Masters Theses

"Because of its unique ability to maintain high flow-ability and remain homogeneous, self-consolidating concrete (SCC) has the potential to significantly reduce the costs associated with civil infrastructure; however, the use of higher paste and lower coarse aggregate volumes than non-SCC concretes raises concerns about shear strength of SCC mixes. This research focused on the components that contribute to the concrete's ability to provide shear by aggregate interlock. Variables investigated by push-off tests included concrete compressive strength, coarse aggregate type , and volumetric content level of the coarse aggregate portion . Post-failure digital imaging software was used to confirm fresh concrete …


Effects Of High Volumes Of Fly Ash On Cement Paste, Karl Wehking Beckemeier Jan 2012

Effects Of High Volumes Of Fly Ash On Cement Paste, Karl Wehking Beckemeier

Masters Theses

"The study of high-volume fly ash (HVFA) concrete mixtures has become popular due to the significant environmental and economic benefits which the material may provide. By including fly ash at 50 percent or greater replacement levels, substantial benefits could be obtained. However, the inclusion of fly ash can have negative effects, including incompatibilities between constituents of a mixture. As the fly ash replacement level increases, the degree and likelihood of these problems increases.

In this study, paste mixtures were made, as part of a larger HVFA concrete study, in order to determine the degree to which varying levels of fly …


Modeling Forward Base Camps As Complex Adaptive Sociotechnical Systems, Lori Ann Miller Jan 2012

Modeling Forward Base Camps As Complex Adaptive Sociotechnical Systems, Lori Ann Miller

Masters Theses

Work for this thesis focuses on managing complexity within complex adaptive sociotechnical systems by using model based systems engineering and virtual engineering tools. The hypothesis of the work is that integrated virtual models can be used to increase the understanding of these complex adaptive sociotechnical systems, resulting in a reduction in the perceived complexity. This was tested by the use of a two factor survey given to experts of a system (the customer and members of the model design team) and to a target user-group. This group received a demonstration and had hands on experience with a preliminary model of …


Path Planning For General Mazes, Grant Gilbert Arthur Rivera Jan 2012

Path Planning For General Mazes, Grant Gilbert Arthur Rivera

Masters Theses

Path planning is used in, but not limited to robotics, telemetry, aerospace, and medical applications. The goal of the path planning is to identify a route from an origination point to a destination point while avoiding obstacles. This path might not always be the shortest in distance as time, terrain, speed limits, and many other factors can affect the optimality of the path. However, in this thesis, the length, computational time, and the smoothness of the path are the only constraints that will be considered with the length of the path being the most important. There are a variety of …


Reliability Evaluation Of Distribution Systems Containing Renewable Distributed Generations, Abdulaziz Abddullah Alkuhayli Jan 2012

Reliability Evaluation Of Distribution Systems Containing Renewable Distributed Generations, Abdulaziz Abddullah Alkuhayli

Masters Theses

Reliability evaluation of distribution networks, including islanded microgrid cases, is presented. The Monte Carlo simulation algorithm is applied to a test network. The network includes three types of distributed energy resources solar photovoltaic (PV), wind turbine (WT) and gas turbine (GT). These distributed generators contribute to supply part of the load during grid-connected mode, but supply the entire load during islanded microgrid operation. PV and WT stochastic models have been used to simulate the randomness of these resources. This study shows that the implementation of distributed generations can improve the reliability of the distribution networks.


Stochastic Model For Solar Sensor Array Data, Faris Alfaris Jan 2012

Stochastic Model For Solar Sensor Array Data, Faris Alfaris

Masters Theses

Statistical approaches are often used in time series analysis, for example, to predict the future trend of a time series. Trend forecasting can be applied in many time related parameters such as: solar radiation, generation of electricity and other variables related to time series to improve the efficiency and to set the design requirements. Since the design of any solar energy system requires knowledge of the availability of solar radiation data at the location of interest. Therefore, this research seeks the application of a statistical model to fit the solar radiation time series and predict the future values. There are …


The Effects Of Water On Sympathetic Detonation And Dead Pressing Of Dynamite And Emulsions, Adam Michael Doerfler Jan 2012

The Effects Of Water On Sympathetic Detonation And Dead Pressing Of Dynamite And Emulsions, Adam Michael Doerfler

Masters Theses

Dynamite and emulsions are very effective explosives in blasting; however they do have some shortcomings. Dynamite is prone to sympathetic detonation whereas emulsions are prone to dead pressing. While this does not happen all the time, the conditions in which the explosives are used do have an effect on whether or not they will sympathetically detonate or dead press.

Numerous researchers have investigated sympathetic detonation for a relationship between the distance between charges, hole separation distance, and size of explosive. This research aimed to look at how hole separation distance was affected when water was introduced into the boreholes for …