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2015

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Full-Text Articles in Engineering

Guest Editorial: The 2014 Capstone Design Conference, Steven Beyerlein, Jay R. Goldberg, Susannah Howe, Scott Palo, Renee Rogge, R. Keith Stanfill Jan 2015

Guest Editorial: The 2014 Capstone Design Conference, Steven Beyerlein, Jay R. Goldberg, Susannah Howe, Scott Palo, Renee Rogge, R. Keith Stanfill

Biomedical Engineering Faculty Research and Publications

The goal of the 2014 Capstone Design Conference held in Columbus, OH was to build upon the success of three previous conferences (2007 and 2010 in Boulder, CO, and 2012 in Champaign, IL) and expand the community of educators, students, and industry members engaged in discussing, analyzing, and improving capstone design education. Sessions at the 2014 Capstone Design Conference were designed for vibrant sharing of ideas and experiences across the capstone community via interactive panel sessions, poster session socials, and hands-on workshops. This editorial discusses conference planning, structure, and feedback. Technical papers that follow in this issue document scholarship surrounding …


A Study Of The Electronics And Software Industry In Ireland 1960-2010, Sarah Davis Jan 2015

A Study Of The Electronics And Software Industry In Ireland 1960-2010, Sarah Davis

Theses

This study explores the origins of the Electronics/ Software industrial sector in the Republic of Ireland and its subsequent development from 1960 to 2010 inclusive. A key focus of the study is to identify and explore the sectoral drivers/inhibitors. The influence of government policy and technical education on this development is explored. This research study was sponsored by the Irish American Partnership.

A critical realist philosophical approach is chosen to deal with the time-frame and the subject area breadth. An evolutionary research design process is used. An ongoing literature review and access to historical documentation provides other contextual data. Roadmapping …


Dynamic Behavior Of Operational Wind Turbines Considering Aerodynamic And Seismic Load Interaction, Mohammad-Amin Asareh Jan 2015

Dynamic Behavior Of Operational Wind Turbines Considering Aerodynamic And Seismic Load Interaction, Mohammad-Amin Asareh

Doctoral Dissertations

"With the advancements in the wind energy production industry, the demand for a cost effective and safe design of wind turbine structures is growing rapidly. The wide deployment of wind turbines in locations with high seismic hazard has lead engineers to take into account a more comprehensive seismic design of such structures. In response to the need for a computational tool that can perform coupled simulations of wind and seismic loads, a seismic module has been developed for the publicly available National Renewable Energy Laboratory (NREL) code, FAST, at the first step of this research. This achievement allows engineers working …


Dissolution Of Borate Glasses And Precipitation Of Phosphate Compounds, Jaime Lynn George Jan 2015

Dissolution Of Borate Glasses And Precipitation Of Phosphate Compounds, Jaime Lynn George

Doctoral Dissertations

"Borate glasses have been developed for biomedical applications such as scaffolds for soft tissue and bone repair. The dissolution processes of borate glasses in phosphate-containing aqueous solutions were studied by µ-Raman spectroscopy which provided information about the types and concentrations of borate species released into the solution as a function of time and characterized the formation of calcium phosphate reaction products on the glass surface. Boric acid molecules (H3BO3) and borate anions (B(OH)4-) can be detected in solution and their relative concentrations depend on the solution pH.

Static and dynamic single-pass flow-through experiments …


Event Sampled Optimal Adaptive Regulation Of Linear And A Class Of Nonlinear Systems, Avimanyu Sahoo Jan 2015

Event Sampled Optimal Adaptive Regulation Of Linear And A Class Of Nonlinear Systems, Avimanyu Sahoo

Doctoral Dissertations

In networked control systems (NCS), wherein a communication network is used to close the feedback loop, the transmission of feedback signals and execution of the controller is currently carried out at periodic sampling instants. Thus, this scheme requires a significant computational power and network bandwidth. In contrast, the event-based aperiodic sampling and control, which is introduced recently, appears to relieve the computational burden and high network resource utilization. Therefore, in this dissertation, a suite of novel event sampled adaptive regulation schemes in both discrete and continuous time domain for uncertain linear and nonlinear systems are designed.

Event sampled Q-learning and …


Resistance Switching Of Electrodeposited Cuprous Oxide, Sanaz Yazdanparast Jan 2015

Resistance Switching Of Electrodeposited Cuprous Oxide, Sanaz Yazdanparast

Doctoral Dissertations

In this work, the resistance switching behavior of electrodeposited cuprous oxide (Cu2O) thin films in Au/Cu2O/top electrode (Pt, Au-Pd, Al) cells was studied. After an initial FORMING process, the fabricated cells show reversible switching between a low resistance state (16.6 Ω) and a high resistance state (0.4 x 106 Ω). Changing the resistance states in cuprous oxide films depends on the magnitude of the applied voltage which corresponds to unipolar resistance switching behavior of this material. The endurance and retention tests indicate a potential application of the fabricated cells for nonvolatile resistance switching random access …


Localization And Tracking Of Electronic Devices With Their Unintended Emissions, Nurbanu Guzey Jan 2015

Localization And Tracking Of Electronic Devices With Their Unintended Emissions, Nurbanu Guzey

Doctoral Dissertations

"The precise localization and tracking of electronic devices via their unintended emissions has a broad range of commercial and security applications. Active stimulation of the receivers of such devices with a known signal generates very low power unintended emissions. This dissertation presents localization and tracking of multiple devices using both simulation and experimental data in the form of five papers.

First the localization of multiple emitting devices through active stimulation under multipath fading with a Smooth MUSIC based scheme in the near field region is presented. Spatial smoothing helps to separate the correlated sources and the multipath fading and results …


Bob R.O.S.S. (Robot Overhead Super Sketcher), Justin Cox, Steven Guest Jan 2015

Bob R.O.S.S. (Robot Overhead Super Sketcher), Justin Cox, Steven Guest

Electrical and Computer Engineering

Objectives

  • Create a large scale image while entertaining people that are watching
  • Design the system to be portable
  • Provide a low-cost alternative to large-scale printers and large digital displays
  • Learn how to design and implement a system that uses a standardized instruction language (G-code)


Enhancing Safety Management System In An Offshore Aviation Company, Nazmus Saqib Jan 2015

Enhancing Safety Management System In An Offshore Aviation Company, Nazmus Saqib

Chulalongkorn University Theses and Dissertations (Chula ETD)

The main aim of the research is to enhance the safety management system through the introduction and tracking of safety performance indicator “non-compliance per flight hour”. All the non-compliances related to the main operational departments were gathered from the data base of the case study company for the year 2014. It was found that the non-compliances per flight hour were highest from the Aircraft Maintenance Department with the exact number being 3.30 non-compliances per flight hour. The scope of this research was therefore focused on the Aircraft Maintenance Department. Aircraft maintenance is a large department so the next step in …


Improvement Of Flat Concrete Roof Tile Manufacturing Process, Korkiat Wiratkapan Jan 2015

Improvement Of Flat Concrete Roof Tile Manufacturing Process, Korkiat Wiratkapan

Chulalongkorn University Theses and Dissertations (Chula ETD)

The objective of this research is to improve the manufacturing process of a concrete roof tile manufacturing company to solve its problems of low labour productivity, rising labour costs and scarcity of labour. Initial analysis established that press forming was a bottleneck in the overall process and used the most manpower. Process activity mapping and Work study were used as tools to analyse the problems to identify non-value-added activities. The seven wastes technique was then applied to define the wastes in the manufacturing process. Improvement alternatives were identified with the aid of the ECRS technique and Lean tools, and these …


Size Effects In Human Visual Inspection For Micro/Meso Scale Parts, Sri Harsha Kavuri Jan 2015

Size Effects In Human Visual Inspection For Micro/Meso Scale Parts, Sri Harsha Kavuri

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Visual inspection has been a major method of quality control in conventional manufacturing processes for the last fifty years. Utilizing trained human inspectors to perform this visual inspection has been the most effective means of maintaining quality control. Extensive research has been performed to understand the factors that influence the human inspection process.

In the recent years, there has been a significant emphasis on manufacturing at the smaller end of the size-spectrum such as Micro and Meso scale manufacturing. Quality control at becomes a challenging task due to the extremely small sizes. Several automated visual inspection techniques have been proposed …


Influence Of Spatial Variations Of Railroad Track Stiffness And Material Inclusions On Fatigue Life, Celestin Nkundineza Jan 2015

Influence Of Spatial Variations Of Railroad Track Stiffness And Material Inclusions On Fatigue Life, Celestin Nkundineza

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Railroad transportation is very important for economic growth and effective maintenance is one critical factor for its economic sustainability. The high repetitive forces from a moving railcar induce cyclic stresses that lead to rail bending and potential deterioration due to fatigue crack initiation and propagation. Previous research for prediction of fatigue life has been done under the assumptions of a uniform track bed and a homogeneous rail. However the spatial variation of the track stiffness is expected to increase the maximum stresses in the rail and, therefore, accelerate the fatigue process. The research described in this dissertation is focused on …


Automated Daily Pattern Filtering Of Measured Building Performance Data, Clayton Miller, Zoltán Nagy, Arno Schlueter Jan 2015

Automated Daily Pattern Filtering Of Measured Building Performance Data, Clayton Miller, Zoltán Nagy, Arno Schlueter

Research Collection College of Integrative Studies

The amount of sensor data generated by modern building systems is growing rapidly. Automatically discovering the structure of diurnal patterns in this data supports implementation of building commissioning, fault detection and retrofit analysis techniques. Additionally, these data are crucial to informing design professionals about the efficacy of their assumptions and strategies used in performance prediction simulation models. In this paper, we introduce DayFilter, a day-typing process that uses Symbolic Aggregate approXimation (SAX), motif and discord extraction, and clustering to detect the underlying structure of building performance data. Discords, or infrequent daily patterns, are filtered and tagged for deeper, detailed analysis …


Automating The Process Of Fabricating Uniform-Sized Cell Spheroids For Three-Dimensional Bioprinting, Ganesh Sosale Jan 2015

Automating The Process Of Fabricating Uniform-Sized Cell Spheroids For Three-Dimensional Bioprinting, Ganesh Sosale

Theses and Dissertations

Although researchers have been able to print small, simple, and avascular tissues, they have been unsuccessful in creating large, complex and vascularized organs. Printing large and complex three-dimensional tissues or organs involves utilizing a large quantity of cellular spheroids and layer-by-layer addition of spheroids. In this study, an in-house cell spheroid fabrication system was developed to produce cell spheroids with human liver cells (hepG2), human endothelial cells (hEC), human neural stem cells (hNSC), and induced pluripotent stem cells (iPSC). It offers the ability of fabricating uniform-sized spheroids repeatedly, which is essential when large and complex structures need to be produced. …


Multi-Platform Arabinoxylan Scaffolds As Potential Wound Dressing Materials, Donald C. Aduba Jr Jan 2015

Multi-Platform Arabinoxylan Scaffolds As Potential Wound Dressing Materials, Donald C. Aduba Jr

Theses and Dissertations

Biopolymers are becoming more attractive as advanced wound dressings because of their naturally derived origin, abundance, low cost and high compatibility with the wound environment. Arabinoxylan (AX) is a class of polysaccharide polymers derived from cereal grains that are primarily used in food products and cosmetic additives. Its application as a wound dressing material has yet to be realized. In this two-pronged project, arabinoxylan ferulate (AXF) was fabricated into electrospun fibers and gel foams to be evaluated as platforms for wound dressing materials. In the first study, AXF was electrospun with varying amounts of gelatin. In the second study, AXF …


The Synthesis Of Solid Supported Palladium Nanoparticles: Effective Catalysts For Batch And Continuous Cross Coupling Reactions, Kendra W. Brinkley Jan 2015

The Synthesis Of Solid Supported Palladium Nanoparticles: Effective Catalysts For Batch And Continuous Cross Coupling Reactions, Kendra W. Brinkley

Theses and Dissertations

Catalysis is one of the pillars of the chemical industry. While the use of catalyst is typically recognized in the automobile industry, their impact is more widespread as; catalysts are used in the synthesis of 80% of the US commercial chemicals. Despite the improved selectivity provided by catalyst, process inefficiencies still threaten the sustainability of a number of synthesis methods, especially in the pharmaceutical industry. Recyclable solid supported catalysts offer a unique opportunity to address these inefficiencies. Such systems coupled with continuous synthesis techniques, have the potential to significantly reduce the waste to desired product ratio (E-factor) of the production …


Measurements And Modeling Of Hydrocarbon Mixture Fluid Properties Under Extreme Temperature And Pressure Conditions, Babatunde A. Bamgbade Jan 2015

Measurements And Modeling Of Hydrocarbon Mixture Fluid Properties Under Extreme Temperature And Pressure Conditions, Babatunde A. Bamgbade

Theses and Dissertations

Knowledge of thermodynamic fluid properties, such as density and phase behavior, is important for the design, operation, and safety of several processes including drilling, extraction, transportation, and separation that are required in the petroleum. The knowledge is even more critical at extreme temperature and pressure conditions as the search for more crude oil reserves lead to harsher conditions. Currently, there is dearth of experimental data at these conditions and as such, the predictive capability of the existing modeling tools are unproven. The objective of this research is to develop a fundamental understanding of the impact of molecular architecture on fluid …


Spatio-Temporal Modeling Of Anatomic Motion For Radiation Therapy, Elizabeth Zachariah Jan 2015

Spatio-Temporal Modeling Of Anatomic Motion For Radiation Therapy, Elizabeth Zachariah

Theses and Dissertations

In radiation therapy, it is imperative to deliver high doses of radiation to the tumor while reducing radiation to the healthy tissue. Respiratory motion is the most significant source of errors during treatment. Therefore, it is essential to accurately model respiratory motion for precise and effective radiation delivery. Many approaches exist to account for respiratory motion, such as controlled breath hold and respiratory gating, and they have been relatively successful. They still present many drawbacks. Thus, research has been expanded to tumor tracking.

The overall goal of 4D-CT is to predict tumor motion in real time, and this work attempts …


Generation And Delivery Of Charged Aerosols To Infant Airways, Landon T. Holbrook Jan 2015

Generation And Delivery Of Charged Aerosols To Infant Airways, Landon T. Holbrook

Theses and Dissertations

The administration of pharmaceutical aerosols to infants on mechanical ventilation needs to be improved by increasing the efficiency of delivery devices and creating better ways of evaluating potential therapies. Aerosolized medicines such as surfactants have been administered to ventilated infants with mixed results, but studies have shown improvement in respiratory function with a much lower dose than with liquid instillation through an endotracheal tube (ETT). An aerosolized medicine must be transported through the ventilation tubing and deposit in the lungs to have the desired therapeutic response.

This work has taken a systematic approach to (i) develop new devices for the …


A Study To Evaluate Non-Uniform Phase Maps In Shape Memory Alloys Using Finite Element Method, Naren Motte Jan 2015

A Study To Evaluate Non-Uniform Phase Maps In Shape Memory Alloys Using Finite Element Method, Naren Motte

Theses and Dissertations

The unique thermo-mechanical behavior of Shape Memory Alloys (SMAs), such as their ability to recover the original shape upon heating or being able to tolerate large deformations without undergoing plastic transformations, makes them a good choice for actuators.

This work studies their application in the aerospace and defense industries where SMA components can serve as release mechanisms for gates of enclosures that have to be deployed remotely. This work provides a novel approach in evaluating the stress and heat induced change of phase in a SMA, in terms of the transformation strain tensor. In particular, the FEA tool

ANSYS has …


Micro- And Macro-Scale Modeling Of Filter Aging: Effects Of Particle Poly-Dispersity And Fiber Cross-Sectional Shape, Ahmed M. Saleh Jan 2015

Micro- And Macro-Scale Modeling Of Filter Aging: Effects Of Particle Poly-Dispersity And Fiber Cross-Sectional Shape, Ahmed M. Saleh

Theses and Dissertations

The goal of this study is to further advance the state of the art in developing self-sufficient methods to predict the performance of an aerosol filter. The simulation methods developed in this study are based on first principles and consequently, they do not rely on empirical correction factors. These simulation methods can be used to predict the instantaneous collection efficiency and pressure drop of a filter under dust-loading conditions. In the current study, 3-D micro- and macroscale CFD models are developed to simulate the service life of flat-sheet and pleated filters. These CFD micro- and macroscale models are also used …


Computational Modeling To Assess Surgical Procedures For The Treatment Of Adult Acquired Flatfoot Deformity, Brian A. Smith Jan 2015

Computational Modeling To Assess Surgical Procedures For The Treatment Of Adult Acquired Flatfoot Deformity, Brian A. Smith

Theses and Dissertations

Several surgically corrective procedures are considered to treat Adult Acquired Flatfoot Deformity (AAFD) patients, relieve pain, and restore function. Procedure selection is based on best practices and surgeon preference. Recent research created patient specific models of Adult Acquired Flatfoot Deformity (AAFD) to explore their predictive capabilities and examine effectiveness of the surgical procedure used to treat the deformity. The models’ behavior was governed solely by patient bodyweight, soft tissue constraints, and joint contact without the assumption of idealized joints. The current work expanded those models to determine if an alternate procedure would be more effective for the individual. These procedures …


The Effects Of Fatigue On Lower Extremity Kinetics And Kinematics In Subjects With Known Ankle Instability, Lindsay E. Clayton Jan 2015

The Effects Of Fatigue On Lower Extremity Kinetics And Kinematics In Subjects With Known Ankle Instability, Lindsay E. Clayton

Theses and Dissertations

The goal of this study was to evaluate biomechanical differences between healthy subjects and those with ankle instability during the gradual onset of lower extremity fatigue from a landing activity. An understanding of these differences is needed in order to prevent future injury to or further debilitation in individuals with ankle instability. A functional fatiguing activity was designed to focus fatigue on the quadriceps muscles, as those are the muscles most frequently fatigued during sport. Measures were taken throughout the progression of fatigue with a force plate and a motion tracking system and included vertical ground reaction force and lower …


Censoring And Fusion In Non-Linear Distributed Tracking Systems With Application To 2d Radar, Armond S. Conte Ii Jan 2015

Censoring And Fusion In Non-Linear Distributed Tracking Systems With Application To 2d Radar, Armond S. Conte Ii

Theses and Dissertations

The objective of this research is to study various methods for censoring state estimate updates generated from radar measurements. The generated 2-D radar data are sent to a fusion center using the J-Divergence metric as the means to assess the quality of the data. Three different distributed sensor network architectures are considered which include different levels of feedback. The Extended Kalman Filter (EKF) and the Gaussian Particle Filter (GPF) were used in order to test the censoring methods in scenarios which vary in their degrees of non-linearity. A derivation for the direct calculation of the J-Divergence using a particle filter …


Integrated Nanoscale Imaging And Spatial Recognition Of Biomolecules On Surfaces, Congzhou Wang Jan 2015

Integrated Nanoscale Imaging And Spatial Recognition Of Biomolecules On Surfaces, Congzhou Wang

Theses and Dissertations

Biomolecules on cell surfaces play critical roles in diverse biological and physiological processes. However, conventional bulk scale techniques are unable to clarify the density and distribution of specific biomolecules in situ on single, living cell surfaces at the micro or nanoscale. In this work, a single cell analysis technique based on Atomic Force Microscopy (AFM) is developed to spatially identify biomolecules and characterize nanomechanical properties on single cell surfaces. The unique advantage of these AFM-based techniques lies in the ability to operate in situ (in a non-destructive fashion) and in real time, under physiological conditions or controlled micro-environments.

First, AFM-based …


Peracetic Acid Sterilization Of Electrospun Polycaprolactone Scaffolds, Suyog Yoganarasimha Jan 2015

Peracetic Acid Sterilization Of Electrospun Polycaprolactone Scaffolds, Suyog Yoganarasimha

Theses and Dissertations

Sterilization of tissue engineered scaffolds is an important regulatory issue and is at the heart of patient safety. With the introduction of new biomaterials and micro/nano structured scaffolds, it is critical that the mode of sterilization preserve these built-in features. Conventional sterilization methods are not optimal for engineered polymeric systems and hence alternate systems need to be identified and validated. PCL is polyester with a low melting point (heat labile), susceptible to hydrolysis and is popular in tissue engineering. Electrospinning generates some nanoscale features within the scaffold, the integrity of which can be affected by sterilization method. Chapter 1 explores …


Peracetic Acid: A Practical Agent For Sterilizing Heat-Labile Polymeric Tissue-Engineering Scaffolds, William R. Trahan Jan 2015

Peracetic Acid: A Practical Agent For Sterilizing Heat-Labile Polymeric Tissue-Engineering Scaffolds, William R. Trahan

Theses and Dissertations

Advanced biomaterials and sophisticated processing technologies aim to fabricate tissue-engineering scaffolds that can predictably interact within a biological environment at a cellular level. Sterilization of such scaffolds is at the core of patient safety and is an important regulatory issue that needs to be addressed prior to clinical translation. In addition, it is crucial that meticulously engineered micro- and nano- structures are preserved after sterilization. Conventional sterilization methods involving heat, steam and radiation are not compatible with engineered polymeric systems because of scaffold degradation and loss of architecture. Using electrospun scaffolds made from polycaprolactone (PCL), a low melting polymer, and …


Modification And Evaluation Of A Brain Computer Interface System To Detect Motor Intention, Christopher V. Hagerty-Hoff Jan 2015

Modification And Evaluation Of A Brain Computer Interface System To Detect Motor Intention, Christopher V. Hagerty-Hoff

Theses and Dissertations

It is widely understood that neurons within the brain produce electrical activity, and electroencephalography—a technique used to measure biopotentials with electrodes placed upon the scalp—has been used to observe it. Today, scientists and engineers work to interface these electrical neural signals with computers and machines through the field of Brain-Computer Interfacing (BCI). BCI systems have the potential to greatly improve the quality of life of physically handicapped individuals by replacing or assisting missing or debilitated motor functions. This research thus aims to further improve the efficacy of the BCI based assistive technologies used to aid physically disabled individuals. This study …


Femtosecond Laser Beam Propagation Through Corneal Tissue: Evaluation Of Therapeutic Laser-Stimulated Second And Third-Harmonic Generation, William R. Calhoun Iii Jan 2015

Femtosecond Laser Beam Propagation Through Corneal Tissue: Evaluation Of Therapeutic Laser-Stimulated Second And Third-Harmonic Generation, William R. Calhoun Iii

Theses and Dissertations

One of the most recent advancements in laser technology is the development of ultrashort pulsed femtosecond lasers (FSLs). FSLs are improving many fields due to their unique extreme precision, low energy and ablation characteristics. In the area of laser medicine, ophthalmic surgeries have seen very promising developments. Some of the most commonly performed surgical operations in the world, including laser-assisted in-situ keratomileusis (LASIK), lens replacement (cataract surgery), and keratoplasty (cornea transplant), now employ FSLs for their unique abilities that lead to improved clinical outcome and patient satisfaction.

The application of FSLs in medical therapeutics is a recent development, and although …


Incorporating Public Perceptions Into The Selection Of A Nuclear Fuel Cycle, John M. Swanson Jan 2015

Incorporating Public Perceptions Into The Selection Of A Nuclear Fuel Cycle, John M. Swanson

Theses and Dissertations

The final disposal location for used nuclear fuel in the U.S. remains unresolved. A major complication in resolving this issue has historically been the lack of public acceptance. This motivates the creation of a decision making model for selecting a nuclear fuel cycle in the U.S. that incorporates the preferences of the public. A model based on the Analytic Hierarchy Process (AHP) was created, tested, and shown to be problematic in incorporating public opinion into decision objectives. A new model based on Multi-Attribute Utility Theory (MAUT) has been created. This model contains the fundamental objectives for both technical and non-technical …