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Branched And Spiral Organic Nanotubes Based On The Self-Assembly Of Bile Acids, Xuejun Zhang 2010 University of Central Florida

Branched And Spiral Organic Nanotubes Based On The Self-Assembly Of Bile Acids, Xuejun Zhang

Electronic Theses and Dissertations

The self-assembly of chiral amphiphilic molecules in aqueous solutions is of particular interest because the chirality of individual molecules is often expressed in their supermolecular structures. Self-assembled tubes made of chiral amphiphilic molecules represent useful supramolecular architectures which hold promise as controlled release vehicles for drug delivery, encapsulates for functional molecules, and nanoreactors for chemical reactions. Lithocholic acid (LCA) is a secondary bile acid with the concentration being identical to that of cholesterol in the hepatic bile and gallbladder. It has a rigid, nearly planar hydrophobic steroid nucleus, with four hydrogen atoms and one hydroxyl group directed toward the concave ...


Power Metal-Oxide-Semiconductor Field-Effect Transistor With Strained Silicon And Silicon Germanium Channel, Shan Sun 2010 University of Central Florida

Power Metal-Oxide-Semiconductor Field-Effect Transistor With Strained Silicon And Silicon Germanium Channel, Shan Sun

Electronic Theses and Dissertations

With the development of modern electronics, the demand for high quality power supplies has become more urgent than ever. For power MOSFETs, maintaining the trend of reducing on-state resistance (conduction loss) without sacrificing switching performance is a severe challenge. In this work, our research is focused on implementing strained silicon and silicon germanium in power MOFETs to enhance carrier mobility, thus achieving the goal of reducing specific on-state resistance. We propose an N-channel super-lattice trench MOSFET, a P-channel sidewall channel trench MOSFET and P-Channel LDMOS with strained Si/SiGe channels. A set of fabrication processes highly compatible with conventional Si ...


Optical Control Of Ultrafast Spin -Wave Relaxation By Magnetic Anisotropy In A Ferromagnet, Kevin James Smith 2010 College of William & Mary - Arts & Sciences

Optical Control Of Ultrafast Spin -Wave Relaxation By Magnetic Anisotropy In A Ferromagnet, Kevin James Smith

Dissertations, Theses, and Masters Projects

This thesis presents an investigation of the damping of spin waves in ferromagnetic Au(3 nm)/Ni(10 nm)/MgO(001) thin films using the time-resolved Magneto-optical Kerr Effect (TR-MOKE) and ferromagnetic resonance (FMR) techniques. In the optical measurements, a 150 fs, 800 nm laser beam pulse is split into pump and probe components. The pump pulse, containing most of the beam energy, thermally excites coherent spin precession. The weaker probe pulse, time-delayed by a variable beam path, captures the magnetization dynamics via the polar MOKE effect, and oscillations are observed as a function of external field amplitude and direction ...


Quantitative Comparison And Modeling Of Urban Storm Water Mass Loadings In The City Of Lincoln, Nebraska, Patrick R. Hartman 2010 University of Nebraska at Lincoln

Quantitative Comparison And Modeling Of Urban Storm Water Mass Loadings In The City Of Lincoln, Nebraska, Patrick R. Hartman

Civil Engineering Theses, Dissertations, and Student Research

QUANTITATIVE ANALYSIS AND MODELING OF URBAN STORM WATER MASS LOADINGS IN THE CITY OF LINCOLN, NEBRASKA

Patrick Ryan Hartman, M. S. University of Nebraska, 2010

Advisors: Bruce I. Dvorak, David M Admiraal

The main goal of this study is to monitor, and then compare results related to the water quality and mass loadings of several constituents at two sites in Lincoln, NE. Differences in water quality were assessed using matched-pair t-tests. Mass loadings were examined using cumulative mass plots, and a predictive model for total suspended solids (TSS) was developed at both sites using real-time data obtained from a USGS ...


Impacts Of Crop, Biomass Harvest Systems, And Nutrient Management On Yield And Subsurface Drainage Water Quality, Matthew J. Helmers, Carl H. Pederson, Ann K. Staudt, Reid Christianson, Antonio P. Mallarino 2010 Iowa State University

Impacts Of Crop, Biomass Harvest Systems, And Nutrient Management On Yield And Subsurface Drainage Water Quality, Matthew J. Helmers, Carl H. Pederson, Ann K. Staudt, Reid Christianson, Antonio P. Mallarino

Iowa State Research Farm Progress Reports

Grain-crop biomass and perennial grass biomass are of particular interest for their use in bioenergy production systems. Nutrient needs, particularly nitrogen and phosphorus, change with varying cropping systems, harvest systems, and rates of fertilizer application. Furthermore, manure generated from livestock production can be a viable nutrient source for cropping systems, reducing the need for commercial fertilizers. The primary focus of this study was to investigate nutrient loss, primarily nitrate-nitrogen loss, in subsurface drainage water under a variety of cropping, nutrient management, and harvest scenarios. Overall crop yields and biomass production were also evaluated.


Near Infrared Photovoltaic Micro-Cell For Optical Fibre Based Power Harvesting, Gary Allwood 2010 Edith Cowan University

Near Infrared Photovoltaic Micro-Cell For Optical Fibre Based Power Harvesting, Gary Allwood

Theses : Honours

A photonic power system using a silicon or germanium based device as a photonic power converter was proposed. The properties of each device were investigated to determine the optimum structure, design, configuration and efficiency for power conversion. These included, but were not limited to, device geometry, doping concentration and the wavelength of the incident beam. Relevant inferences were made from the results obtained and compared to previous work. Currently, research into photovoltaic power converters is focused on the efficiencies of complex heterostuctures made from gallium-arsenide compounds. Here, the properties of a silicon device were investigated in detail as the predicted ...


Complex Systems Architecting Using Design Primitives, Comparative Analysis And Fuzzy Analytical Feedback, Jason Paul Dauby, Cihan H. Dagli 2010 Missouri University of Science and Technology

Complex Systems Architecting Using Design Primitives, Comparative Analysis And Fuzzy Analytical Feedback, Jason Paul Dauby, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

Modern systems are increasing in complexity. It is advantageous to understand and control this complexity as early in the design lifecycle as possible. The system architecting community must reconcile the inherent ambiguity in a system description with the need for analytical assessments of system attributes so as to increase the likelihood of developmental success. Presently, it is commonplace to decompose systems and subsystems using assumptions of idealized severability and reliance on superposition to estimate composite performance. It is suggested that these assumptions can result in errant oversimplification and represent an opportunity for new systems engineering research. This paper introduces a ...


Analysis Of Periodic Structures Using Finite-Difference Time-Domain Method, Khaled ElMahgoub 2010 University of Mississippi

Analysis Of Periodic Structures Using Finite-Difference Time-Domain Method, Khaled Elmahgoub

Electronic Theses and Dissertations

Periodic structures are of great importance in electromagnetics these days due to their wide range of applications such as frequency selective surfaces (FSS), electromagnetic band gap, periodic absorbers, metamaterials and many others. The aim of this work is to develop several algorithms to analyze different types of electromagnetic periodic structures using the constant horizontal wavenumber finite-difference time-domain periodic boundary condition (FDTD/PBC). A new FDTD/PBC approach is introduced to analyze the scattering properties of general skewed grid periodic structures. The approach is simple to implement and efficient in terms of both computational time and memory usage. In addition, an ...


Crack Detectability And Durability Of Coaxial Cable Sensors In Reinforced Concrete Bridge Applications, Genda Chen, Ryan D. McDaniel, Michael A. Brower, David Pommerenke 2010 Missouri University of Science and Technology

Crack Detectability And Durability Of Coaxial Cable Sensors In Reinforced Concrete Bridge Applications, Genda Chen, Ryan D. Mcdaniel, Michael A. Brower, David Pommerenke

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The working mechanism and the measurement principle of topology-based crack sensors made of coaxial cables are briefly reviewed. The sensitivity, spatial resolution, and ruggedness of two coaxial cable sensors, respectively made of rubber and Teflon dielectric materials, were compared and validated with laboratory testing of a 4/5-scale, T-shaped, reinforced concrete beam-column specimen. Two Teflon sensors were installed on one of the solid decks of a three-span continuous highway bridge to investigate their durability and measurement repeatability. Laboratory tests indicated that both types of sensors have high sensitivity, but the Teflon sensor has a higher spatial resolution and a negligible ...


Impaired Vascular Reactivity Following Chronic Ischemia In The Arteries Of The Mouse Hindlimb, Thomas (Tom) Kesler 2010 California Polytechnic State University, San Luis Obispo

Impaired Vascular Reactivity Following Chronic Ischemia In The Arteries Of The Mouse Hindlimb, Thomas (Tom) Kesler

Biomedical Engineering

Collateral dependent hyperemia is reduced following chronic ischemia, but the contribution of individual vessel reactivity is unknown. Further, it is not known what aspect of the complex ischemic injury response impacts vascular reactivity. To determine the impact of ischemia on vascular reactivity, we measured functional vasodilation in the muscular branch artery following resection of the femoral artery proximal to the muscular branch. On day-14 after surgery the diameter of the muscular branch was measured using side-stream dark field (SDF) imaging intravital microscopy. At moderate intensity skeletal muscle contraction (1mA, 200µs, 8Hz, 90sec), functional vasodilation is reduced compared to the contralateral ...


Study Of Stability Of Time-Domain Features For Electromyographic Pattern Recognition, Dennis Tkach, He Huang, Todd A. Kuiken 2010 University of Rhode Island

Study Of Stability Of Time-Domain Features For Electromyographic Pattern Recognition, Dennis Tkach, He Huang, Todd A. Kuiken

Department of Electrical, Computer, and Biomedical Engineering Faculty Publications

Background: Significant progress has been made towards the clinical application of human-machine interfaces (HMIs) based on electromyographic (EMG) pattern recognition for various rehabilitation purposes. Making this technology practical and available to patients with motor deficits requires overcoming real-world challenges, such as physical and physiological changes, that result in variations in EMG signals and systems that are unreliable for long-term use. In this study, we aimed to address these challenges by (1) investigating the stability of time-domain EMG features during changes in the EMG signals and (2) identifying the feature sets that would provide the most robust EMG pattern recognition.

Methods ...


Computational Structural Modelling Of Coronary Stent Deployment: A Review, David Martin, Fergal Boyle 2010 Technological University Dublin

Computational Structural Modelling Of Coronary Stent Deployment: A Review, David Martin, Fergal Boyle

Articles

The finite element (FE) method is a powerful investigative tool in the field of biomedical engineering, particularly in the analysis of medical devices such as coronary stents whose performance is extremely difficult to evaluate in vivo. In recent years, a number of FE studies have been carried out to simulate the deployment of coronary stents, and the results of these studies have been utilised to assess and optimise the performance of these devices. The aim of this paper is to provide a thorough review of the state-of-the-art research in this area, discussing the aims, methods and conclusions drawn from a ...


Drug-Eluting Stents For Coronary Artery Disease: A Review, David Martin, Fergal Boyle 2010 Technological University Dublin

Drug-Eluting Stents For Coronary Artery Disease: A Review, David Martin, Fergal Boyle

Articles

Over the past decade the introduction of drug-eluting stents (DESs) has revolutionised the treatment of coronary artery disease. However, in recent years concern has arisen over the long-term safety and efficacy of DESs due to the occurrence of late adverse clinical events such as stent thrombosis. With this concern in mind, research and development is currently centred on increasing the long-term safety and efficacy of DESs. The aim of this paper is to provide a thorough review of currently approved and promising investigational DESs. With dozens of companies involved in the development of new and innovative anti-restenotic agents, polymeric coatings ...


Inverse Optimal Control As A Tool To Understand Human Yoyo Playing, Katja Mombaur, Manish Sreenivasa 2010 University of Heidelberg

Inverse Optimal Control As A Tool To Understand Human Yoyo Playing, Katja Mombaur, Manish Sreenivasa

Faculty of Engineering and Information Sciences - Papers: Part B

This paper presents an inverse optimal control approach to identify objective functions of human motion from motion capture measurements. We apply it to analyze human yoyo playing. Yoyo playing may seem easy to us to learn but it is a challenging problem from a mechanical point of view involving a hybrid dynamics model. We recorded vertical yoyo playing of humans measuring yoyo height and rotation angle as well as the corresponding hand motions. Results of inverse optimal control are presented showing a mixed criterion of cycle time and terms depending on yoyo and hand acceleration and velocity.


Investigating An Optimal Decision Point For Probability Bounds Analysis Models When Used To Estimate Remedial Soil Volumes Under Uncertainty At Hazardous Waste Sites, Charles O. Dankwah 2010 Walden University

Investigating An Optimal Decision Point For Probability Bounds Analysis Models When Used To Estimate Remedial Soil Volumes Under Uncertainty At Hazardous Waste Sites, Charles O. Dankwah

Walden Dissertations and Doctoral Studies

Hazardous waste site remediation cost estimation requires a good estimate of the contaminated soil volume. The United States Environmental Protection Agency (U.S. EPA) currently uses deterministic point values to estimate soil volumes but the literature suggests that probability bounds analysis (PBA) is the more accurate method to make estimates under uncertainty. The underlying statistical theory is that they are more accurate than deterministic estimates because probabilistic estimates account for data uncertainties. However, the literature does not address the problem of selecting an optimal decision point from the interval-valued PBA estimates. The purpose of this study was to identify the ...


Infrared Thermography-Driven Flaw Detection And Evaluation Of Hot Mix Asphalt Pavements, Yong K. Cho, Yong-Rak Kim, Thaddaeus Bode 2010 University of Nebraska-Lincoln

Infrared Thermography-Driven Flaw Detection And Evaluation Of Hot Mix Asphalt Pavements, Yong K. Cho, Yong-Rak Kim, Thaddaeus Bode

Nebraska Department of Transportation Research Reports

This research was conducted to study more realistic explanations of how variables are created and dealt with during hot mix asphalt (HMA) paving construction. Several paving projects across the state of Nebraska have been visited where sensory devices were used to test how the selected variables contribute to temperature differentials including density, moisture content within the asphalt, material surface temperature, internal temperature, wind speed, haul time, and equipment type. Areas of high temperature differentials are identified using an infrared camera whose usefulness was initially confirmed with a penetrating thermometer. A non-nuclear density device was also used to record how the ...


Practical Simulation Application: Evaluation Of Process Control Parameters In Twisted-Pair Cables Manufacturing System, Amr Mahfouz, Said Hassan, Amr Arisha 2010 Technological University Dublin

Practical Simulation Application: Evaluation Of Process Control Parameters In Twisted-Pair Cables Manufacturing System, Amr Mahfouz, Said Hassan, Amr Arisha

Articles

Intensive competition and rapid technology development of Twisted-Pair Cables (TPC) industry have left no room for competing manufacturers to harbour system inefficiencies. TPC are used in various communication and networks hardware applications; their manufacturing facilities face many challenges including various product configurations with different equipment settings, different product flows and Work in Process (WIP) space limitations. The quest for internal efficiency and external effectiveness forces companies to align their internal settings and resources with external requirements/orders, or in different words, significant factors must be set appropriately and identified prior to manufacturing processes. Integrated definition models (IDEF0, IDEF3) in conjunction ...


The Analysis Of Rush Orders Risk In Supply Chain: A Simulation Approach, Amr Arisha, Amr Mahfouz 2010 Technological University Dublin

The Analysis Of Rush Orders Risk In Supply Chain: A Simulation Approach, Amr Arisha, Amr Mahfouz

Conference papers

Satisfying customers by delivering demands at agreed time, with competitive prices, and in satisfactory quality level are crucial requirements for supply chain survival. Incident of risks in supply chain often causes sudden disruptions in the processes and consequently leads to customers losing their trust in a company’s competence. Rush orders are considered to be one of the main types of supply chain risks due to their negative impact on the overall performance. Using integrated definition modeling approaches (i.e. IDEF0 & IDEF3) and simulation modeling technique , a comprehensive integrated model has been developed to assess rush order risks and examine ...


A Computational Analysis Of Cognitive Effort, Luca Longo, Stephen Barrett 2010 Technological University Dublin

A Computational Analysis Of Cognitive Effort, Luca Longo, Stephen Barrett

Books/Book Chapters

Cognitive effort is a concept of unquestionable utility in understanding human behaviour. However, cognitive effort has been defined in several ways in literature and in everyday life, suffering from a partial understanding. It is common to say “Pay more attention in studying that subject” or “How much effort did you spend in resolving that task?”, but what does it really mean? This contribution tries to clarify the concept of cognitive effort, by introducing its main influencing factors and by presenting a formalism which provides us with a tool for precise discussion. The formalism is implementable as a computational concept and ...


Forty Years Of Movie Hacking: Considering The Potential Implications Of The Popular Media Representation Of Computer Hackers From 1968 To 2008, Damian Gordon 2010 Technological University Dublin

Forty Years Of Movie Hacking: Considering The Potential Implications Of The Popular Media Representation Of Computer Hackers From 1968 To 2008, Damian Gordon

Articles

Increasingly movies are being produced which feature plots that incorporate elements of computer security and hacking, and cumulatively these movies are creating a public perception as to the nature of computer security. This research examines movies that feature hackers (and hacking) to identify if any common themes emerge from these movies in their representation of these issues. To achieve this, first a corpus of hacking movies is created, and then using a qualitative data analysis technique, guidelines are developed which distinguish those movies that actually have the potential to create a perception with the general public. The resultant dataset is ...


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