Digital Commons Network^™

A Novel Cantilever For Bi-Harmonic Atomic Force Microscopy, Muthukumaran Loganathan

Masters Theses

"Tapping mode (TM) AFM is a popularly used AFM technique in which an oscillating sharp tip mounted on a micro cantilever is used to probe the surface of interest with nanoscale resolution by making intermittent (tapping) contact with the surface. Any change in surface profile affects the tip amplitude, and is detectable only if it results in an amplitude change that is significant enough to be measured by the laser detector. Hence, it is desirable to have a micro cantilever that is sensitive to surface changes so as to provide sharper images and better surface resolution.

In the first part …

Design Of A Vortex Induced Vibration Based Marine Hydro-Kinetic Energy System, Varun Michael Lobo

Masters Theses

"Hydrokinetic energy harvesting based on vortex induced vibration (VIV) of a bluff body is discussed. VIV is defined as the vibration incurred on a bluff body due to an external fluid flowing over it. These vibrations are the results of boundary layer separation from the surface of the body. An optimized VIV generator has been developed, that utilizes a non-contact type linear magnetic device for generation of energy. The cylinder was chosen such that at the mass ratio (m*) was always lower than the critical mass (m*_critical= 0.52). The studies were based on two complementary …

Transient Growth And Instability Control Using Iteration-Varying Filter Ilc In Flexible Dual Flywheel System, Tong Mu

Masters Theses

"In the field of precision motion control, many industrial systems have flexible modes. This is especially true for very high performance nanopositioning systems where traditional bearing systems are replaced with flexible structures in order to eliminate sliding friction. The precision motion control is difficult in flexible systems because the rapid phase transition around the resonant frequency must be accurately modeled in order to actively control the resonant motion. In order to experimentally study the effectiveness of various control algorithms on flexible systems, a dual-flywheel flexible system is constructed. The mechatronics system design strategy is presented in this thesis. The control …

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 …

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 …

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 …

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 …

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 …

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 …

Semantic Preserving Text Tepresentation And Its Applications In Text Clustering, Michael Howard

Masters Theses

Text mining using the vector space representation has proven to be an valuable tool for classification, prediction, information retrieval and extraction. The nature of text data presents several issues to these tasks, including large dimension and the existence of special polysemous and synonymous words. A variety of techniques have been devised to overcome these shortcomings, including feature selection and word sense disambiguation. Privacy preserving data mining is also an area of emerging interest. Existing techniques for privacy preserving data mining require the use of secure computation protocols, which often incur a greatly increased computational cost. In this paper, a generalization-based …

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 …

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 …

Effects Of Four Commercially Available Fxa Proteins On The Fluorogenic Anti-Fxa Assay When Monitoring Unfractionated Heparin, Vanessa Castro-Lopez, Brian Murray, Leanne F. Harris, James S. O'Donnell, Anthony J. Killard

Articles

Four commercially available Factor Xa (FXa) reagents were evaluated in a fluorogenic anti-FXa assay. The four reagents - of which three were of human origin and the fourth was bovine - were compared in terms of the resulting assay dynamic ranges, lag times, CV and R2 values, sum of squares as well as their sensitivity to unfractionated heparin (UFH) within the therapeutic range of 0-1.2 U mL-1. Based on a balance of performance characteristics, an optimum reagent was selected which had the best combination of all parameters. The best performing serine endopeptidase in the fluorogenic anti-FXa assay was found to …

Designing Wise Communities That Engage In Creative Problem Solving: An Analysis Of An Online Design Model, Charlotte Nirmalani Gunawardena, Ludmila Layne, Casey Frechette

University Libraries & Learning Sciences Faculty and Staff Publications

Addressing the conference theme of “design thinking,” this paper discusses an instructional design model, WisCom (Wisdom Communities) that we developed to build a wise learning community online, to solve open-ended, ill-structured problems such as solving a health crisis or an environmental disaster, which requires the exchange of multiple perspectives, inter-disciplinary thinking, creative problem solving, and social construction of knowledge. Based on socio-constructivist, sociocultural theories of learning and mediated cognition (Vygotsky, 1978), distributed cognition (Hutchins, 1995; Pea, 1993), group cognition (Stahl, 2006), research on how people learn (Bransford, Vye, Bateman, Brophy, & Roselli, 2004), and distance education design principles (Moore & …

Logistics Modeling And Project Management Practices For Contingency Basing, Amanda Jo Gealy

Masters Theses

"Contingency basing is a critical factor in mission success but requires significant logistical and commander support. Designing and constructing a camp that is safe, secure, and self-sustaining can be a difficult task for a Contingency Basing engineering manager. The infrastructure for basic needs such as electricity, fuel, water, food, and waste management is critical and needs to be flexible.

This research focuses on assisting the Contingency Basing engineering manager in designing and constructing a feasible base camp using project management and modeling tools. Measuring scalability and resiliency with in the contingency base was studied as well. The methodology concentrates on …

A Decentralized Fault Diagnosis And Prognosis Scheme For Nonlinear Interconnected Systems, Deepthi Shreeya Lathamaheswari Raja

Masters Theses

"Today's systems are getting more complex with a significant number of variables to be monitored for information processing to aid in fault diagnosis and prognosis. Centralized diagnosis and prognosis schemes are not preferred for such complex systems as they lead to delayed or missed alarms and possibly catastropic [sic] failures. Instead, this thesis addresses a decentralized fault diagnosis and prognosis scheme both in continuous and discrete-time for nonlinear complex systems which can be divided into smaller subsystems. Such complex systems are referred to as a large-scale interconnected nonlinear system. This thesis is presented in the form of two papers first …

Distributed And Collaborative Watermarking In Relational Data, Prakash Kumar

Masters Theses

"Watermarking relational data is an important topic in the field of copyright protection, given the increasing prevalence of piracy and illegal duplication of databases. While there exists solutions for watermarking relational data, the problems that arise due to multiple ownership (two or more) of databases have not been acknowledged. This research focuses on developing a novel watermarking scheme to counter the problems. The watermarking scheme proposed necessitates the owners of the database in consideration to come together to perform the watermarking process. The scheme can be applied to insert watermarks in both numerical and categorical data. The watermarking scheme is …

Integration Of Multiple Vision Systems And Toolbox Development, Rohit Vijay Bapat

Masters Theses

"Depending on the required coverage, multiple cameras with different fields of view, positions and orientations can be employed to form a motion tracking system. Correctly and efficiently designing and setting up a multi-camera vision system presents a technical challenge. This thesis describes the development and application of a toolbox that can help the user to design a multi-camera vision system. Using the parameters of cameras, including their positions and orientations, the toolbox can calculate the volume covered by the system and generate its visualization for a given tracking area. The cameras can be repositioned and reoriented using toolbox to generate …

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 …

A Study Of Wavelet-Based Noise Reduction Techniques In Mammograms, Varun Shah

Masters Theses

"Breast cancer is one of the most common cancers and claims over one thousand lives every day. Breast cancer turns fatal only when diagnosed in late stages, but can be cured when diagnosed in its early stages. Over the last two decades, Digital Mammography has served the diagnosis of breast cancer. It is a very powerful aid for early detection of breast cancer. However, the images produced by mammography typically contain a great amount noise from the inherent characteristics of the imaging system and the radiation involved. Shot noise or quantum noise is the most significant noise which emerges as …

Gray Gas Analysis Of Radiative Preheating Effects On Shock Induced Combustion, Pratibha Raghunandan

Masters Theses

"The use of detonations in combustors has been receiving increased attention in recent times. The presence of shock waves in such combustors invariably poses the existence of two domains that present different physics for the flow processes. The variation of upstream temperature due to radiative heating by the products of combustion was given particular attention in the present study. The modeling of heat transfer across a normal shock wave of negligible thickness was done by considering the reactants and the products of combustion to be in radiative equilibrium with each other. The quantification of emissivity of the products of combustion …

Maximum Power Point Tracking Control Of Hydrokinetic Turbine And Low-Speed High-Thrust Permanent Magnet Generator Design, Hailong Zhou

Masters Theses

"River-based hydrokinetic turbine power generation systems have been studied to introduce an effective energy flow control method. Hydrokinetic turbine systems share a lot of similarities with wind turbine systems in terms of physical principles of operation, electrical hardware, and variable speed capability for optimal energy extraction. A multipole permanent magnet synchronous generator is used to generate electric power because of its ability to reach high power density and high thrust at low speed. A 3-phase diode rectifier is used to convert AC power from the generator into DC power and a boost converter is used to implement energy flow control. …

Physiochemical Characteristics Contributing To The Cytotoxicity Of Transition Metal Oxides, Chi-Heng Wu

Masters Theses

"In the past ten years nanotechnology has not only evolved to play a prominent role in our economy but also increased the concern over potential adverse effects caused by nanomaterials to human health and the environment. Nanotoxicity is to understand the nature and origin of the toxicity imposed by nanomaterials. Studies from our laboratory have shown that nanoparticle induces oxidative stress, perturbs calcium homeostasis, alter gene expression, and produces pro-inflammatory responses. We also identified a trend of toxicity: TiO₂ < Cr₂O₃ < Fe₂O₃ < Mn₂O₃ < NiO < ZnO < CuO. We then asked a question: what are physiochemical factors of transition metal nanoparticles that contributed to this increasing cytotoxicity. In this thesis I investigated the correlation between physicochemical properties and toxicity of the transition metal oxides in the 4th Period of the Periodic Table of Elements. Particle size, BET surface area, point of zero charge, metal dissolution, and degree of surface adsorption of transition metal oxide nanoparticles were measured. There were no increasing trends in both particle size and specific surface area. The point of zero charge showed an increasing trend as TiO₂ < Cr₂O₃ < Fe₂O₃ < NiO < CuO = ZnO < Mn₂O₃. The number of available binding sites of nanoparticle showed an increasing trend as Cr₂O₃ > ZnO > CuO > NiO > Fe₂O₃ > Mn₂O₃ > TiO₂. The degree of adsorption on the surface of nanoparticles showed an increasing trend with atomic …

3d Spatio-Temporal Analysis For Compressive Sensing In Magnetic Resonance Imaging Of The Murine Cardiac Cycle, Brice Aaron Hirst

Masters Theses

"This thesis consists of two major contributions, each of which has been prepared in a conference paper. These papers will be submitted for publication in the SPIE 2013 Medical Imaging Conference and the ASEE 2013 Annual Conference.

The first paper explores a three-dimensional compressive sensing (CS) technique for reducing measurement time in MR imaging of the murine (mouse) cardiac cycle. By randomly undersampling a single 2D slice of a mouse heart at regular time intervals as it expands and contracts through the stages of a heartbeat, a CS reconstruction algorithm can be made to exploit transform sparsity in time as …

Cooperative Power Control Approaches Towards Fair Radio Resource Allocation For Wireless Network, Liuju Wu

Masters Theses

"Performance optimization in wireless networks is a complex problem due to variability and dynamics in network topology and density, traffic patterns, mutual interference, channel uncertainties, etc. Opportunistic or selfish approaches may result in unbalanced allocation of channel capacity where particular links are overshadowed. This degrades overall network fairness and hinders a multi-hop communication by creating bottlenecks. A desired approach should allocate channel capacity proportionally to traffic priority in a cooperative manner. This work consists of two chapters that address the fairness share problem in wireless ad hoc, peer-to-peer networks and resource allocation within Cognitive Radio network. In the first paper, …

5-Axis Tool Path Generation With Collision Detection For Finish Machining Of Freeform Surfaces, Jomy Francis

Masters Theses

"Research in the field of Tool path generation for freeform surfaces has been done intensively in the past. However, the main challenge that still exists is the computational efficiency related to the tool path generation. Tool path generation for freeform surface involves instantaneous calculation of new tool orientations which does not collide with the neighboring surfaces. Since the collision check of tool and neighboring surface is done repetitively at every instant of the tool, the calculations at every instant are to be computationally as easy as possible.

This thesis is composed of one paper. Paper I presents a novel extension …

Laboratory Implementations Of Pmsm Drive In Hybrid Electric Vehicles Applications, Amir E. Saad

Masters Theses

"Field Programmable Gate Arrays (FPGAs) are one of the today's most successful technologies for developing systems that require real time operation and providing additional flexibility to the designer. This research is focused on developing a control board for a permanent magnet synchronous machine (PMSM) using an FPGA module. The board is configured for individual use of an FPGA, digital signal processor (DSP) or in combination to control the PMSM by generating the required Pulse Width Modulator (PWM) to the inverter in order to drive and control the speed of the PMSM. Since, the exact rotor position and speed are required …

Should Any Workplace Be Exempt From Smoke-Free Law: The Irish Experience, M. Mccaffrey, Patrick J. Goodman, A. Gavigan, C. Kenny, C. Hogg, L. Byrne, J. Mcloughlin, Luke Clancy

Articles

Background.

In 2004, the Irish Government introduced national legislation banning smoking in workplaces; with exemptions for “a place of residence”. This paper summarises three Irish studies of exempted premises; prisons, psychiatric hospitals and nursing homes. Methods. PM2.5 and nicotine were measured in nursing homes and psychiatric hospitals, in addition to ultrafine particles in the hospitals. In the prisons, officers (n = 30) completed exhaled breath Carbon Monoxide (CO) measurements. Questionnaires determined officers’ opinion on introducing smoking prohibitions in prisons. Nursing home smoking policies were examined and questionnaires completed by staff regarding workplace secondhand smoke (SHS) exposure. Findings. Ultrafine particle concentrations …

Effect On Diagnostic Image Quality Of 3d Warping Registration Algorithms For Mr Angiography In The Lower Legs, Andrew Fagan, Daniel Foley, Jacinta Browne, Barry Sheane, Dearbhail O'Driscoll, Niall Sheehy, James Meaney

Articles

No abstract provided.

Impaired Cleanance And Enhanced Pulmonary Inflammatory/Fibrotic Response To Carbon Nanotubes In Myeloperoxidase-Deficient Mice, Anna A. Shvedova, Alexandr A. Kapralov, Wei Hong Feng, Elena R. Kisin, Ashley R. Murray, Robert R. Mercer, Claudette M. St. Croix, Megan A. Lang, Simon C. Watkins, Nagarjun V. Konduru, Brett L. Allen, Jennifer Conroy, Gregg P. Kotchey, Bashir M. Mohamed, Aidan Meade, Yuri Volkov, Alexander Star, Bengt Fadeel, Valerian E. Kagan

Articles

Advancement of biomedical applications of carbonaceous nanomaterials is hampered by their biopersistence and pro-inflammatory action in vivo. Here, we used myeloperoxidase knockout B6.129X1-MPO (MPO k/o) mice and showed that oxidation and clearance of single walled carbon nanotubes (SWCNT) from the lungs of these animals after pharyngeal aspiration was markedly less effective whereas the inflammatory response was more robust than in wild-type C57Bl/6 mice. Our results provide direct evidence for the participation of MPO – one of the key-orchestrators of inflammatory response – in the in vivo pulmonary oxidative biodegradation of SWCNT and suggest new ways to control the biopersistence …