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Bennett Clocking Of Nanomagnetic Logic Using Multiferroic Single-Domain Nanomagnets, Jayasimha Atulasimha, Supriyo Bandyopadhyay 2010 Virginia Commonwealth University

Bennett Clocking Of Nanomagnetic Logic Using Multiferroic Single-Domain Nanomagnets, Jayasimha Atulasimha, Supriyo Bandyopadhyay

Mechanical and Nuclear Engineering Publications

The authors show that it is possible to rotate the magnetization of a multiferroic (strain-coupled two-layer magnetostrictive-piezoelectric)nanomagnet by a large angle with a small electrostatic potential. This can implement Bennett clocking [Int. J. Theor. Phys.21, 905 (1982)] in nanomagnetic logic arrays resulting in unidirectional propagation of logic bits from one stage to another. This method is potentially more energy efficient than using spin-transfer torque for magnetization rotation. For realistic parameters, it is shown that a potential of ∼0.2 V applied to a multiferroicnanomagnet can rotate magnetization by nearly 90° to implement Bennett clocking.


Accelerated Aging Of Mwcnt Filled Electrically Conductive Adhesives, Ashwanth Reddy Vangala 2010 University of Kentucky

Accelerated Aging Of Mwcnt Filled Electrically Conductive Adhesives, Ashwanth Reddy Vangala

University of Kentucky Master's Theses

Electrically conductive adhesives (ECA) are discussed and studied with everincreasing interest as an environmentally friendly alternative to solder interconnection in microelectronics circuit packaging. They are used to attach surface mount devices (SMD), Integrated Circuits (IC) and Flip chips in electronic assembly. The use of ECAs brings some benefits like flexibility, mild processing conditions and process simplicity. Multi walled carbon nanotubes (MWCNT) are used instead of metal fillers because of their novel properties such as light weight, high aspect ratio, corrosion resistant, reduced processing temperature, lead free, good electrical conduction and mechanical strength.

The purpose of the present work is to ...


Laminar-Turbulent Transition For Attached And Separated Flow, Qian Zhang 2010 University of Kentucky

Laminar-Turbulent Transition For Attached And Separated Flow, Qian Zhang

University of Kentucky Doctoral Dissertations

A major challenge in the design of turbomachinery components for aircraft gas turbine engines is high cycle fatigue failures due to flutter. Of particular concern is the subsonic/transonic stall flutter boundary which occurs at part speed near the stall line. At these operating conditions the incidence angle is large and the relative Mach number is high subsonic or transonic. Viscous effects dominate for high incidence angles.

In order to predict the flutter phenomena, accurate calculation of the steady and unsteady aerodynamic loading on the turbomachinery airfoils is necessary. The development of unsteady aerodynamic models to predict the unsteady forces ...


Hot Water, Dry Streams: A Tale Of Two Trout, Jack R. Tuholske 2010 Vermont Law School

Hot Water, Dry Streams: A Tale Of Two Trout, Jack R. Tuholske

All In-Stream Flows Material

Norman Maclean’s timeless memoir A River Runs Through It begins with the reflection that in his household “there was no clear line between religion and fly fishing.”1 That zeal remains today; nearly 30 million Americans call themselves fishermen.2 Anglers devoted an aggregate of 517 million user-days pursuing their passion in 2006 and spent billions of dollars to support it.3 Fishing in the western United States holds a special place in fishing lore the world over and for good reason. From the great trout waters of Montana, to the salmon-laden rivers of the west coast, to the ...


A Comparative Guide To The Western States' Public Trust Doctrines: Public Values, Private Rights, And The Evolution Toward An Ecological Public Trust, Robin Kundis Craig 2010 The Florida State College of Law

A Comparative Guide To The Western States' Public Trust Doctrines: Public Values, Private Rights, And The Evolution Toward An Ecological Public Trust, Robin Kundis Craig

All In-Stream Flows Material

In the arid West, balancing private needs for fresh water to consume against the public values-recreational, aesthetic, and ecological-served by leaving fresh water in situ has tended to favor the private use side. Evidence of this result is both massive and minor, ranging from California's multi-billion-dollar water transportation system,1 to the routine de-watering of the Colorado River so that little to no water reaches the Sea of Cortez,2 to water-related Endangered Species Act lawsuits in dozens of watersheds. 3


Humanoid Human-Like Reaching Control Based On Movement Primitives, Minh Tuan Tran, Philippe Souères, Michel Taix, Manish Sreenivasa, Christophe Halgand 2010 Universite Paul Sabatier

Humanoid Human-Like Reaching Control Based On Movement Primitives, Minh Tuan Tran, Philippe Souères, Michel Taix, Manish Sreenivasa, Christophe Halgand

Faculty of Engineering and Information Sciences - Papers: Part B

This paper deals with the problem of generating realistic human-like reaching movements from a small set of movement primitives. Two kinds of movement databases are used as reference. The first one is obtained numerically, by applying biological principles of motor control on the dynamic model of the robot arm. The second one is obtained by recording reaching movements of human subjects. From these databases, primitives are extracted and analyzed by using Principal Component Analysis. An original generalization method is then proposed for generating movements that did not belong to the initial database. We show that twenty primitives allow to produce ...


Real-Time Model Predictive Control Of Quasi-Keyhole Pipe Welding, Kun Qian 2010 University of Kentucky

Real-Time Model Predictive Control Of Quasi-Keyhole Pipe Welding, Kun Qian

University of Kentucky Doctoral Dissertations

Quasi-keyhole, including plasma keyhole and double-sided welding, is a novel approach proposed to operate the keyhole arc welding process. It can result in a high quality weld, but also raise higher demand of the operator. A computer control system to detect the keyhole and control the arc current can improve the performance of the welding process. To this effect, developing automatic pipe welding, instead of manual welding, is a hot research topic in the welding field.

The objective of this research is to design an automatic quasi-keyhole pipe welding system that can monitor the keyhole and control its establishment time ...


Design And Performance Analysis Of Genetic Algorithms For Topology Control Problems, Cem Safak Sahin 2010 The Graduate Center, City University of New York

Design And Performance Analysis Of Genetic Algorithms For Topology Control Problems, Cem Safak Sahin

All Dissertations, Theses, and Capstone Projects

In this dissertation, we present a bio-inspired decentralized topology control mechanism, called force-based genetic algorithm (FGA), where a genetic algorithm (GA) is run by each autonomous mobile node to achieve a uniform spread of mobile nodes and to provide a fully connected network over an unknown area. We present a formal analysis of FGA in terms of convergence speed, uniformity at area coverage, and Lyapunov stability theorem.

This dissertation emphasizes the use of mobile nodes to achieve a uniform distribution over an unknown terrain without a priori information and a central control unit. In contrast, each mobile node running our ...


Quality Analysis In Flexible Manufacturing Systems With Batch Productions, Junwen Wang 2010 University of Kentucky

Quality Analysis In Flexible Manufacturing Systems With Batch Productions, Junwen Wang

University of Kentucky Doctoral Dissertations

To improve product quality and reduce cost, batch production is often implemented in many exible manufacturing systems. However, the current literature does not provide any method to analyze the quality performance in a flexible manufacturing system with batch production.

In this research, we present an analytical method with closed-form formula to evaluate the quality performance in such systems. Based on the model, we discover and investigate monotonic and non-monotonic properties in quality to provide practical guidance for operation management. To improve product quality, we introduce the notions of quality improvability with respect to product sequencing. In addition, we develop the ...


Digital Inpainting Algorithms And Evaluation, Vijay Venkatesh Mahalingam 2010 University of Kentucky

Digital Inpainting Algorithms And Evaluation, Vijay Venkatesh Mahalingam

University of Kentucky Doctoral Dissertations

Digital inpainting is the technique of filling in the missing regions of an image or a video using information from surrounding area. This technique has found widespread use in applications such as restoration, error recovery, multimedia editing, and video privacy protection. This dissertation addresses three significant challenges associated with the existing and emerging inpainting algorithms and applications. The three key areas of impact are 1) Structure completion for image inpainting algorithms, 2) Fast and efficient object based video inpainting framework and 3) Perceptual evaluation of large area image inpainting algorithms.

One of the main approach of existing image inpainting algorithms ...


Nanoscale Functionalization And Characterization Of Surfaces With Hydrogel Patterns And Biomolecules, Hariharasudhan Chirra Dinakar 2010 University of Kentucky

Nanoscale Functionalization And Characterization Of Surfaces With Hydrogel Patterns And Biomolecules, Hariharasudhan Chirra Dinakar

University of Kentucky Doctoral Dissertations

The advent of numerous tools, ease of techniques, and concepts related to nanotechnology, in combination with functionalization via simple chemistry has made gold important for various biomedical applications. In this dissertation, the development and characterization of planar gold surfaces with responsive hydrogel patterns for rapid point of care sensing and the functionalization of gold nanoparticles for drug delivery are highlighted.

Biomedical micro- and nanoscale devices that are spatially functionalized with intelligent hydrogels are typically fabricated using conventional UV-lithography. Herein, precise 3-D hydrogel patterns made up of temperature responsive crosslinked poly(N-isopropylacrylamide) over gold were synthesized. The XY control of the ...


Near-Field Radiative Transfer: Thermal Radiation, Thermophotovoltaic Power Generation And Optical Characterization, Mathieu Francoeur 2010 University of Kentucky

Near-Field Radiative Transfer: Thermal Radiation, Thermophotovoltaic Power Generation And Optical Characterization, Mathieu Francoeur

University of Kentucky Doctoral Dissertations

This dissertation focuses on near-field radiative transfer, which can be defined as the discipline concerned with energy transfer via electromagnetic waves at sub-wavelength distances. Three specific subjects related to this discipline are investigated, namely nearfield thermal radiation, nanoscale-gap thermophotovoltaic (nano-TPV) power generation and optical characterization. An algorithm for the solution of near-field thermal radiation problems in one-dimensional layered media is developed, and several tests are performed showing the accuracy, consistency and versatility of the procedure. The possibility of tuning near-field radiative heat transfer via thin films supporting surface phononpolaritons (SPhPs) in the infrared is afterwards investigated via the computation of ...


Ablation Of Chronic Total Occlusions Using Kilohertz-Frequency Mechanical Vibrations In Minimally Invasive Angioplasty Procedures., Garrett McGuinness, Mark Wylie, Graham Gavin 2010 Dublin City University

Ablation Of Chronic Total Occlusions Using Kilohertz-Frequency Mechanical Vibrations In Minimally Invasive Angioplasty Procedures., Garrett Mcguinness, Mark Wylie, Graham Gavin

Articles

Certain minimally invasive cardiology procedures, such as balloon angioplasty and stent implantation, critically require that the site of an arterial blockage be crossed by an intraluminal guidewire. Plaques resulting in near or totally occluded arteries are known as chronic total occlusions (CTOs), and crossing them with conventional guidewires is a significant challenge. Among the most promising proposed solutions is the delivery of high power, low frequency ultrasonic vibrations to the occlusion site via an intraluminal wire waveguide. The vibrating distal-tip of the ultrasound wire waveguide is used to transmit energy to the surrounding plaques, tissues and fluids in order to ...


Optimization Models And Algorithms For Spatial Scheduling, Christopher J. Garcia 2010 Old Dominion University

Optimization Models And Algorithms For Spatial Scheduling, Christopher J. Garcia

Engineering Management & Systems Engineering Theses & Dissertations

Spatial scheduling problems involve scheduling a set of activities or jobs that each require a certain amount of physical space in order to be carried out. In these problems space is a limited resource, and the job locations, orientations, and start times must be simultaneously determined. As a result, spatial scheduling problems are a particularly difficult class of scheduling problems. These problems are commonly encountered in diverse industries including shipbuilding, aircraft assembly, and supply chain management. Despite its importance, there is a relatively scarce amount of research in the area of spatial scheduling.

In this dissertation, spatial scheduling problems are ...


Computational Structural Modelling Of Coronary Stent Deployment: A Review, David Martin, Fergal Boyle 2010 Dublin Institute of Technology

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 Dublin Institute of Technology

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 ...


Measurement And Modeling Of Infrared Nonlinear Absorption Coefficients And Laser-Induced Damage Thresholds In Ge And Gasb, T. J. Wagner, M. A. Bohn, Ronald A. Coutu Jr., L. P. Gonzalez, J. M. Murray, K. L. Schepler, S. Guha 2010 Air Force Institute of Technology

Measurement And Modeling Of Infrared Nonlinear Absorption Coefficients And Laser-Induced Damage Thresholds In Ge And Gasb, T. J. Wagner, M. A. Bohn, Ronald A. Coutu Jr., L. P. Gonzalez, J. M. Murray, K. L. Schepler, S. Guha

Electrical and Computer Engineering Faculty Research and Publications

Using a simultaneous fitting technique to extract nonlinear absorption coefficients from data at two pulse widths, we measure two-photon and free-carrier absorption coefficients for Ge and GaSb at 2.05 and 2.5 μm for the first time, to our knowledge. Results agreed well with published theory. Single-shot damage thresholds were also measured at 2.5 μm and agreed well with modeled thresholds using experimentally determined parameters including nonlinear absorption coefficients and temperature dependent linear absorption. The damage threshold for a single-layer Al2O3 anti-reflective coating on Ge was 55% or 35% lower than the uncoated threshold for ...


Experimental And Numerical Analysis Of Fuel Cells, Abul Bashar Mahmud Hasan 2010 Louisiana State University and Agricultural and Mechanical College

Experimental And Numerical Analysis Of Fuel Cells, Abul Bashar Mahmud Hasan

LSU Doctoral Dissertations

Fuel Cells are attractive power source for use in electronic applications. Physical phenomena (water generation, saturation effect in fuel cell, poisoning, and thermal stress) are studied that governs the operation of a Proton Exchange Membrane Fuel Cell (PEMFC) and Solid Oxide Fuel cell (SOFC). Additionally, experimental studies and numerical simulations on PEMFC gas flow channel, the determination of the impact of the single channel fuel cell are presented. Furthermore, preliminary study is done for the application of APS (Air Plasma Spray) to SOFC and adhesion of anode and cathode with electrolytes for the determination of parameters involved in manufacturing the ...


Multiwall Carbon Nanotubes Alter The Thermal Profile And Antibiotic Elution Of Orthopaedic Bone Cement, Alison Carroll Tickle 2010 University of Kentucky

Multiwall Carbon Nanotubes Alter The Thermal Profile And Antibiotic Elution Of Orthopaedic Bone Cement, Alison Carroll Tickle

University of Kentucky Master's Theses

Multiwall carbon nanotubes (MWNTs) have extraordinary mechanical and thermal transport properties. They significantly improve the static and dynamic mechanical properties of acrylic orthopaedic bone cement when added to the dry cement polymer powder. Understanding the role MWNTs play on bone cement polymerization temperatures will lead to improved mechanical integrity of the cement-bone interface in joint arthroplasties. It was determined through thermal testing that MWNTs increased the polymerization time of the methylmethacrylate by 45-460% and decreased the peak exothermic temperature of bone cement with and without antibiotics. The flow of heat produced during polymerizing cement was reduced 25-85% with the addition ...


Verilog Design And Fpga Prototype Of A Nanocontroller System, Akshay Vummannagari 2010 University of Kentucky

Verilog Design And Fpga Prototype Of A Nanocontroller System, Akshay Vummannagari

University of Kentucky Master's Theses

Many new fabrication technologies, from nanotechnology and MEMS to printed organic semiconductors, center on constructing arrays of large numbers of sensors, actuators, or other devices on a single substrate. The utility of such an array could be greatly enhanced if each device could be managed by a programmable controller and all of these controllers could coordinate their actions as a massively-parallel computer. Kentucky Architecture nanocontroller array with very low per controller circuit complexity can provide efficient control of nanotechnology devices.

This thesis provides a detailed description of the control hierarchy of a digital system needed to build "nanocontrollers" suitable for ...


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