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Articles 5191 - 5220 of 13031

Full-Text Articles in Engineering

Lipid Detection In Pig Arteries Using Intravascular Photoacoustic Imaging, Jieying Mai, Yingchun Cao, Ayeeshik Kole, Michael Sturek, Ji-Xin Cheng Aug 2016

Lipid Detection In Pig Arteries Using Intravascular Photoacoustic Imaging, Jieying Mai, Yingchun Cao, Ayeeshik Kole, Michael Sturek, Ji-Xin Cheng

The Summer Undergraduate Research Fellowship (SURF) Symposium

Heart disease is the leading cause of death in the United States and worldwide. Each year over 370,000 people died from coronary artery disease in America. As the primary form of coronary artery disease, atherosclerosis behaves as lipid-rich plaque development inside an artery wall. Vulnerable plaques are those prone to rupture, which may result in thrombus or even death. Typical hallmarks of a vulnerable plaque include thin fibrous cap, a large lipid-rich necrotic core and inflammatory infiltrate. The identification and accurate detection of these lipid depositions in the arterial wall is crucial in the diagnosis of atherosclerosis. However, none of …

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Optimization Of A High-Speed X-Ray Imaging System For Studying Sprays, Lane E. Schultz, Mikhail N. Slipchenko, Terrence R. Meyer, Wilbert C. Slowman Aug 2016

Optimization Of A High-Speed X-Ray Imaging System For Studying Sprays, Lane E. Schultz, Mikhail N. Slipchenko, Terrence R. Meyer, Wilbert C. Slowman

The Summer Undergraduate Research Fellowship (SURF) Symposium

Spray-based liquid atomization and liquid mixing is critical for development of efficient combustors and drug delivery systems as well as multiple coating-related applications. While optical methods allow characterization of low density regions of sprays, the scattering of optical photons hinders the characterization of a dense core. Unlike optical photons, higher-energy X-ray photons have the capability to penetrate and image the core structure of sprays. Here we characterized temporal and spatial resolution of an X-Ray imaging system based on a commercially available tube source with an anode size of 0.6 mm. For high-speed imaging, a phosphor screen in combination with a …

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Quantum Dot Lab : Incorporation Of Alloys In The Capping Layer Of Multi-Layer Quantum Dot, Unmesha U. Kale, Prasad Sarangapani, Jim Fonseca, Gerhard Klimeck Aug 2016

Quantum Dot Lab : Incorporation Of Alloys In The Capping Layer Of Multi-Layer Quantum Dot, Unmesha U. Kale, Prasad Sarangapani, Jim Fonseca, Gerhard Klimeck

The Summer Undergraduate Research Fellowship (SURF) Symposium

Quantum dots have enhanced the performance of several optoelectronic devices. Designing and obtaining optimal quantum dot structures requires intensive simulation. Quantum Dot Lab on nanoHUB provides such a simulation platform. The simulation is fully parallelized and depending on the structure, the tool decides the computational resource which is to be used for the simulation. To obtain accurate predictions of quantum dot structures it is essential to provide a variety of simulation parameters to the user. In this research, a user interface was created where the user can simulate alloys by Random distribution and by Virtual Crystal Approximation(VCA) type distribution in …

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Multi-Objective Optimization Under Uncertainty Using The Hyper-Volume Expected Improvement, Martin Figura, Piyush Pandita, Rohit K. Tripathy, Ilias Bilionis Aug 2016

Multi-Objective Optimization Under Uncertainty Using The Hyper-Volume Expected Improvement, Martin Figura, Piyush Pandita, Rohit K. Tripathy, Ilias Bilionis

The Summer Undergraduate Research Fellowship (SURF) Symposium

The design of real engineering systems requires the optimization of multiple quantities of interest. In the electric motor design, one wants to maximize the average torque and minimize the torque variation. A study has shown that these attributes vary for different geometries of the rotor teeth. However, simulations of a large number of designs cannot be performed due to their high cost. In many problems, design optimization of multi-objective functions is a very challenging task due to the difficulty to evaluate the expectation of the objectives. Current multi-objective optimization (MOO) techniques, e.g., evolutionary algorithms cannot solve such problems because they …

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Tfit Modeling Of Wave Propagation For Flow Excursion, Brachston Grubbs, Krishna Chetty, Martin Bertodano Aug 2016

Tfit Modeling Of Wave Propagation For Flow Excursion, Brachston Grubbs, Krishna Chetty, Martin Bertodano

The Summer Undergraduate Research Fellowship (SURF) Symposium

In the nuclear power industry, the Two-Fluid Model (TFM) is mainly used in the simulation of Loss of Coolant Accident (LOCA). The Two-Fluid Model is a wave mechanics formulation that may also be used to analytically perform stability analysis, which requires numerous assumptions and simplifications. This project aimed to advance the TFIT-TFM simulations in the modeling of the flow excursion instability. By using the TFIT computational code, simulation results can be obtained without the need for assumptions and simplifications. In this project, a simulation was performed to verify the nonlinear wave propagation capability of TFIT. During the verification process, the …

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Effect Of Aggregation And Particle Size On The Thermal Conductivity Of Nickel-Epoxy Nanocomposites, Jacob M. Faulkner, Xiangyu Li, Xiulin Ruan Dr. Aug 2016

Effect Of Aggregation And Particle Size On The Thermal Conductivity Of Nickel-Epoxy Nanocomposites, Jacob M. Faulkner, Xiangyu Li, Xiulin Ruan Dr.

The Summer Undergraduate Research Fellowship (SURF) Symposium

Microprocessor advancements have been stunted in recent years by inadequate means of heat dissipation as power continues to grow and size continues to shrink. One way to increase thermal conductivity while maintaining electrical insulation is to add metal nanoparticles to a polymer matrix. This cheap material has become a popular thermal interface for this reason. However, optimization of the interface is dependent upon a number of factors including particle size, shape, orientation, and aggregation. Various theoretical models and numerical approximations have been developed to find the effective thermal conductivity of such nanocomposites, but none has been able to fully incorporate …

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The Effect Of Honeycomb Cavity: Acoustic Performance Of A Double-Leaf Micro Perforated Panel, Yuxian Huang, Kai Ming Li Aug 2016

The Effect Of Honeycomb Cavity: Acoustic Performance Of A Double-Leaf Micro Perforated Panel, Yuxian Huang, Kai Ming Li

The Summer Undergraduate Research Fellowship (SURF) Symposium

A micro perforated panel (MPP) is a device consisting of a thin plate and submillimeter perforations for reducing low frequency noise. MPPs have many advantages compared to traditional sound absorption materials, such as durability and designability, and they can be used in a variety of places such as room interior designs, passenger and crew compartments of aircrafts and combustion engines. The models in this study were designed and fabricated with the latest 3-D printing technology. The transmission loss and sound absorption coefficient of the 3-D printed double-leaf MPPs with honeycomb cavities were studied. According to the established theory, MPPs work …

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Exploring The Effects Of Aromatic Molecules In Chemical Enhanced Oil Recovery, Jacob M. Crain, Cliff Johnston, Rituraj Borgohain Aug 2016

Exploring The Effects Of Aromatic Molecules In Chemical Enhanced Oil Recovery, Jacob M. Crain, Cliff Johnston, Rituraj Borgohain

The Summer Undergraduate Research Fellowship (SURF) Symposium

Chemical enhanced oil recovery (cEOR) methods are being used as a viable contributor to the world’s growing energy demands. Due to the complex chemical composition of crude oil, attempting to optimize the surfactant concentration and salinity of formulations is done empirically. This process can be very time intensive due to the wide variety of surfactant structures available for cEOR. Surfactant selection is typically done by matching the average chain length of the oil with that of the surfactant. In this study, we are trying to understand how aromatic structures present in Illinois Basin crude oil interact with surfactants. This will …

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Thermoelectric Properties From Ab Initio Calculations, Gustavo Javier-Rico, David M. Guzman, Alejandro H. Strachan Aug 2016

Thermoelectric Properties From Ab Initio Calculations, Gustavo Javier-Rico, David M. Guzman, Alejandro H. Strachan

The Summer Undergraduate Research Fellowship (SURF) Symposium

As nanoscales become accessible to experimentalists, atomistic simulations of materials are becoming increasingly important for the prediction and design of materials properties. Recently, the search for energy efficient materials has driven the development of new theoretical methods, such as the Landauer-Datta-Lundstrom (LDL) generalized transport model, to explore thermoelectric properties of materials based on their electronic structure and lattice dynamics. The Landauer Transport Properties (LanTraP) tool, currently available in nanoHUB, allows the computation of thermoelectric transport coefficients from a full-band electron dispersion; however, generating such electron band structures from ab initio methods is a convoluted process. The aim of this project …

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Cellular Model Of Hydrogen Peroxide Release: In Preparation For On-Chip Sensor Measurements, Sarah M. Libring, Hannah R. Kriscovich, James K. Nolan, Siddarth V. Sridharan, Jose F. Rivera, David B. Janes, Jenna L. Rickus Aug 2016

Cellular Model Of Hydrogen Peroxide Release: In Preparation For On-Chip Sensor Measurements, Sarah M. Libring, Hannah R. Kriscovich, James K. Nolan, Siddarth V. Sridharan, Jose F. Rivera, David B. Janes, Jenna L. Rickus

The Summer Undergraduate Research Fellowship (SURF) Symposium

Hydrogen peroxide is traditionally associated with cellular damage; however, recent studies show that low levels of H2O2 are released by cells as part of normal intercellular communication. The mechanisms of hydrogen peroxide transport, uptake and release, and biological effects are not yet well known but have important implications for cancer, stem cells, and aging. Standard H2O2 assays cannot make spatially or temporally resolved quantitative measurements at a cellular scale. Previously we developed a microelectrode array (MEA) and calibration methods for quantifying H2O2 gradients in space and time. The sensor was validated …

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Laser Assisted Manufacturing: A Comparison Of Mechanical Properties Between Lam And Conventional Manufacturing Techniques, William Blakeslee, Neil S. Bailey, Kyung-Min Hong, Shunyu Liu, Yung C. Shin Aug 2016

Laser Assisted Manufacturing: A Comparison Of Mechanical Properties Between Lam And Conventional Manufacturing Techniques, William Blakeslee, Neil S. Bailey, Kyung-Min Hong, Shunyu Liu, Yung C. Shin

The Summer Undergraduate Research Fellowship (SURF) Symposium

Laser assisted manufacturing methods, such as direct metal deposition (DMD) and laser beam welding (LBW), are promising methods because of their higher precision and greater productivity when compared to traditional manufacturing methods. Because these methods are relatively new, the mechanical properties of samples produced by laser assisted manufacturing are not well understood. In this study the mechanical properties of samples produced by laser assisted manufacturing methods are analyzed and compared with data obtained from traditional manufacturing methods. The DMD process used Fe-TiC and Ti-TiC metal matrix composites, while LBW used AISI 304 stainless steel. The results vary widely with the …

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Exploring Regional And Telecoupled Land Use Change Impacts From Environmental Shocks, Kevin Hill, Liz Wachs, Brady Hardiman, David Yu, Shweta Singh Aug 2016

Exploring Regional And Telecoupled Land Use Change Impacts From Environmental Shocks, Kevin Hill, Liz Wachs, Brady Hardiman, David Yu, Shweta Singh

The Summer Undergraduate Research Fellowship (SURF) Symposium

Natural disasters or environmental shocks have the potential to disrupt local agricultural systems as well as distant agricultural systems through cascading effects. In this work we selected two distinct environmental shocks and traced their cascading effects on land use change. Quantifying cascading effects is a salient issue because climate change forecasts indicate an increase in frequency and intensity of global environmental shocks. This study incorporated the concept of telecoupled systems involving interrelating ecological, economic and political/social components. A telecoupled framework involving cascading effects was implemented using three approaches. The first approach involved using bilateral agricultural trade matrix data to analyze …

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A Fast Model For The Simulation Of External Gear Pumps, Zechao Lu, Xinran Zhao, Andrea Vacca Aug 2016

A Fast Model For The Simulation Of External Gear Pumps, Zechao Lu, Xinran Zhao, Andrea Vacca

The Summer Undergraduate Research Fellowship (SURF) Symposium

External gear pump is an important category of positive displacement fluid machines used to perform the mechanical–hydraulic energy conversions in many fluid power applications. An efficient numerical simulation program is needed to simulate the system in order to provide a direction for design purpose. The model consists of a lumped parameter fluid dynamic model and a model that simulates the radial micro-motions of the gear’s axes of rotation. The system consists of a set of ordinary differential equations related to the conservation on mass of the internal control volumes of the pump, which are given by the tooth space volumes …

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Use Of Demographic Faultlines To Predict Teams’ Conflict, Satisfaction And Performance, Marina Pazeti, Isabel Jimenez-Useche Aug 2016

Use Of Demographic Faultlines To Predict Teams’ Conflict, Satisfaction And Performance, Marina Pazeti, Isabel Jimenez-Useche

The Summer Undergraduate Research Fellowship (SURF) Symposium

During the past decade, industries and businesses have experienced the formation of a global market place. Current tasks require professionals from different fields and with different backgrounds to work together as a team. The goal of this study is to investigate how diversity in teams may impact perception of conflict, satisfaction and performance, in first-year engineering students. Team diversity is associated with faultlines: the potential to form subgroups based on certain characteristics. The strength and width of faultlines in a team is likely to impact the team’s outcomes. In this research, we used demographic characteristics such as gender, ethnicity, language …

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Continuous Ligand-Assisted Elution Chromatography Applied To Separation Of Rare Earth Elements, Jeremy A. Weinstock, David M. Harvey, N.-H. Linda Wang Aug 2016

Continuous Ligand-Assisted Elution Chromatography Applied To Separation Of Rare Earth Elements, Jeremy A. Weinstock, David M. Harvey, N.-H. Linda Wang

The Summer Undergraduate Research Fellowship (SURF) Symposium

Rare earth elements (REEs) are metals used to make many valuable products such as magnets and electronics. Following their extraction from larger materials, REEs are to be separated into their individual components as high purity is required for product manufacture. Purification is very difficult because most (15/17) of the REEs are lanthanides (Ln’s) and Ln ions have the same valence and similar atomic radii. The current industrial process for purifying REEs involves using toxic solvents to perform a series of liquid-liquid extractions. Ling and Wang (2015) proposed a ligand-assisted batch chromatography process to purify Ln’s. The latter approach is a …

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Pathway By Which Vagus Nerve Stimulation Of B Fibers Affects Heart Rate, Kelsey Wasilczuk, Matthew Ward, Pedro Irazoqui Aug 2016

Pathway By Which Vagus Nerve Stimulation Of B Fibers Affects Heart Rate, Kelsey Wasilczuk, Matthew Ward, Pedro Irazoqui

The Summer Undergraduate Research Fellowship (SURF) Symposium

Heart failure (HF) affects over 5 million adults in the United States. Many HF patients have a high resting heart rate, which is correlated with a high mortality rate. In recent years, vagus nerve stimulation (VNS) has become an increasingly researched therapy to reduce the resting heart rate of HF patients. However, current dosage given during VNS is increased incrementally at the doctor’s office until side effects present themselves in a patient. In addition, the means by which the therapy works is not completely understood. To better understand the therapy’s mechanisms, the right cervical vagus nerve of several Long Evans …

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Relative Contributions Of Inelastic Phonon Scattering And Elastic Phonon Scattering To Thermal Boundary Conductance Across Solid Interfaces, Mengxi Zhao, Zexi Lu, Xiulin Ruan Aug 2016

Relative Contributions Of Inelastic Phonon Scattering And Elastic Phonon Scattering To Thermal Boundary Conductance Across Solid Interfaces, Mengxi Zhao, Zexi Lu, Xiulin Ruan

The Summer Undergraduate Research Fellowship (SURF) Symposium

The knowledge of inelastic phonon scattering is crucial for the understanding of thermal boundary conductance across solid interfaces. Several traditional theoretical models such as the acoustic mismatch model (AMM) and the diffuse mismatch model (DMM) assume that the elastic phonon scattering drives the thermal transport across the interface. But there are experiments indicating that the inelastic phonon scattering plays an important part in the interfacial thermal energy conduction as well. We use nonequilibrium molecular dynamics (NEMD) to predict the inelastic phonon conductance across Cu/Si interface. Temperature distribution across Cu/Si interface has been obtained from the simulation results, and a temperature …

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Photonicstd-2d: Modeling Light Scattering In Periodic Multilayer Photonic Structures, Alexey Bondarev, Shaimaa Azzam, Zhaxylyk Kudyshev, Alexander V. Kildishev Aug 2016

Photonicstd-2d: Modeling Light Scattering In Periodic Multilayer Photonic Structures, Alexey Bondarev, Shaimaa Azzam, Zhaxylyk Kudyshev, Alexander V. Kildishev

The Summer Undergraduate Research Fellowship (SURF) Symposium

Efficient modeling of electromagnetic processes in optical and plasmonic metamaterials is important for enabling new and exciting ways to manipulate light for advanced applications. In this work, we put together a tool for numerical simulation of propagation of normally incident light through a nanostructured multilayer composite material. The user builds a unit cell of a given material layer-by-layer starting from a substrate up to a superstrate, splitting each layer further into segments. The segments are defined by width and material -- dielectric, metal or active medium. Simulations are performed with the finite difference time domain (FDTD) method. A database of …

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Design Optimization Of A Stochastic Multi-Objective Problem: Gaussian Process Regressions For Objective Surrogates, Juan Sebastian Martinez, Piyush Pandita, Rohit K. Tripathy, Ilias Bilionis Aug 2016

Design Optimization Of A Stochastic Multi-Objective Problem: Gaussian Process Regressions For Objective Surrogates, Juan Sebastian Martinez, Piyush Pandita, Rohit K. Tripathy, Ilias Bilionis

The Summer Undergraduate Research Fellowship (SURF) Symposium

Multi-objective optimization (MOO) problems arise frequently in science and engineering situations. In an optimization problem, we want to find the set of input parameters that generate the set of optimal outputs, mathematically known as the Pareto frontier (PF). Solving the MOO problem is a challenge since expensive experiments can be performed only a constrained number of times and there is a limited set of data to work with, e.g. a roll-to-roll microwave plasma chemical vapor deposition (MPCVD) reactor for manufacturing high quality graphene. State-of-the-art techniques, e.g. evolutionary algorithms; particle swarm optimization, require a large amount of observations and do not …

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Nanobubbles Provide Theranostic Relief To Cancer Hypoxia, Christopher M. Long, Pushpak N. Bhandari, Joseph Irudayaraj Aug 2016

Nanobubbles Provide Theranostic Relief To Cancer Hypoxia, Christopher M. Long, Pushpak N. Bhandari, Joseph Irudayaraj

The Summer Undergraduate Research Fellowship (SURF) Symposium

Hypoxia is a common motif among tumors, contributing to metastasis, angiogenesis, cellular epigenetic abnormality, and resistance to cancer therapy. Hypoxia also plays a pivotal role in oncological studies, where it can be used as a principal target for new anti-cancer therapeutic methods. Oxygen nanobubbles were designed in an effort to target the hypoxic tumor regions, thus interrupting the hypoxia-inducible factor-1α (HIF-1α) regulatory pathway and inhibiting tumor progression. At less than 100nm, oxygen nanobubbles act as a vehicle for site-specific oxygen delivery, while also serving as an ultrasound contrast agent for advanced imaging purposes. Through in vitro and in vivo studies, …

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Quantification And Characterization Of Aluminum Distributions In Commercial Beta And Mordenite Zeolites By Cobalt Exchange, Rebecca L. Reitzel, Claire T. Nimlos, Rajamani Gounder Aug 2016

Quantification And Characterization Of Aluminum Distributions In Commercial Beta And Mordenite Zeolites By Cobalt Exchange, Rebecca L. Reitzel, Claire T. Nimlos, Rajamani Gounder

The Summer Undergraduate Research Fellowship (SURF) Symposium

The aluminum distribution throughout the zeolite framework determines the structural, ion-exchange and catalytic properties of the zeolite. Several methods have been proposed to control the Al distribution, but in order to accurately assess these methods a procedure is needed to quantify Al distribution in various zeolite frameworks. Co2+ ions exchange onto the zeolite framework at Al pairs, and atomic absorbance spectroscopy (AAS) can be used to quantify the number of exchanged Co2+ ions and, in turn, the overall number of Al pairs. Each framework exhibits differences in pore size and channel configuration which affect the equilibrium conditions needed …

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Reward Modulated Spike Timing Dependent Plasticity Based Learning Mechanism In Spiking Neural Networks, Shrihari Sridharan, Gopalakrishnan Srinivasan, Kaushik Roy Aug 2016

Reward Modulated Spike Timing Dependent Plasticity Based Learning Mechanism In Spiking Neural Networks, Shrihari Sridharan, Gopalakrishnan Srinivasan, Kaushik Roy

The Summer Undergraduate Research Fellowship (SURF) Symposium

Spiking Neural Networks (SNNs) are one of the recent advances in machine learning that aim to further emulate the computations performed in the human brain. The efficiency of such networks stems from the fact that information is encoded as spikes, which is a paradigm shift from the computing model of the traditional neural networks. Spike Timing Dependent Plasticity (STDP), wherein the synaptic weights interconnecting the neurons are modulated based on a pair of pre- and post-synaptic spikes is widely used to achieve synaptic learning. The learning mechanism is extremely sensitive to the parameters governing the neuron dynamics, the extent of …

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Transport Contaminant In Flowing Water For Improving Water Quality, Ghassani Feta Adani, Antoine Aubeneau, Carlo Andrej Alviar, Xuqing Xiong, Shizhang Wang Aug 2016

Transport Contaminant In Flowing Water For Improving Water Quality, Ghassani Feta Adani, Antoine Aubeneau, Carlo Andrej Alviar, Xuqing Xiong, Shizhang Wang

The Summer Undergraduate Research Fellowship (SURF) Symposium

Clean freshwater is fundamental to sustain human activities and the aquatic life. However, cities, industries, and agriculture wastes deteriorate water quality. For example, released fertilizer induces excess algal growth. This leads to major ecological problems such as eutrophication of freshwater ecosystems which has not only a great environmental cost impact, but can also affect the health and sustenance living of the people. This project investigates the transport of nitrate, a major plant fertilizer, in flowing freshwater. Streams and rivers can transform nitrate, thus mitigating its impact. Most of the biogeochemical reactions involved in nitrate removal take place where microorganisms usually …

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Haptic Foot Feedback For Kicking Training In Virtual Reality, Hank Huang, Hong Tan Aug 2016

Haptic Foot Feedback For Kicking Training In Virtual Reality, Hank Huang, Hong Tan

The Summer Undergraduate Research Fellowship (SURF) Symposium

As means to further supplement athletic performances increases, virtual reality is becoming helpful to sports in terms of cognitive training such as reaction, mentality, and game strategies. With the aid of haptic feedback, interaction with virtual objects increases by another dimension, in addition to the presence of visual and auditory feedback. This research presents an integrated system of a virtual reality environment, motion tracking system, and a haptic unit designed for the dorsal foot. The prototype simulates a scenario of virtual kicking and returns haptic response upon collision between the user’s foot and virtual object. The overall system was evaluated …

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X-Ray And Laser Investigation Of High Pressure Sprays, Wilbert C. Slowman, Lane E. Shultz, Terence R. Meyer Aug 2016

X-Ray And Laser Investigation Of High Pressure Sprays, Wilbert C. Slowman, Lane E. Shultz, Terence R. Meyer

The Summer Undergraduate Research Fellowship (SURF) Symposium

The diagnostics of multiphase flows is important to understand the correlation of parameters such as nozzle geometry, flow velocity, liquid breakup characteristics, atomization, and mass distribution. Investigation of each of these parameters can lead to various improvements on design and optimization, for example, of combustion in gas turbines and rocket engines. For this project, the X-ray and optical diagnostics of multiphase flows in propulsion is investigated for high pressures. Two x-ray tube sources are used to illuminate the spray, and the images are captured on phosphor plates coupled to high-speed cameras. Reconstruction of the mass distribution is accomplished using computer …

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Dynamic Behavior Of A Clamped-Clamped Bi-Stable Laminate For Energy Harvesting, Ajay V. Kumar, Andres F. Arrieta Ph.D., Myungwon Hwang Aug 2016

Dynamic Behavior Of A Clamped-Clamped Bi-Stable Laminate For Energy Harvesting, Ajay V. Kumar, Andres F. Arrieta Ph.D., Myungwon Hwang

The Summer Undergraduate Research Fellowship (SURF) Symposium

Multi-stable laminates have many applications in morphing structures, energy harvesting devices, and metamaterials due to the specific characteristics attributed to the exhibited stable states. Changes between stable states allow for large deflections, on-demand variation of the stiffness of compliant structures embedded within these elements, and control of effective dynamic properties in periodic lattices. These changes in state can be accessed via a snap-through instability triggered by introducing a well-defined activation energy. The resulting oscillations could enable broadband energy harvesting via piezoelectric transduction and resistive circuits. In this paper, a clamped-clamped bi-stable laminate is studied to understand the behavior of the …

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Evaluation Of Strain Distortion Correction Protocol Using Scanning Electron Microscopy And Digital Image Correlation, Alexandra Mallory, Alberto Mello, Michael Sangid Aug 2016

Evaluation Of Strain Distortion Correction Protocol Using Scanning Electron Microscopy And Digital Image Correlation, Alexandra Mallory, Alberto Mello, Michael Sangid

The Summer Undergraduate Research Fellowship (SURF) Symposium

Scanning electron microscopy in combination with digital image correlation (SEM-DIC) is a useful technique for measuring strain in materials at the micro-scale. In particular, it can be used to identify micro-scale strain localizations that are the precursor to material failure. While SEM produces high resolution images of the microstructure, the images also contain a large amount of distortion that, during DIC, will result in distorted strain values that require correction. In this project, a nickel-based alloy underwent cyclic mechanical fatigue at three different high temperatures to a targeted maximum strain. Scanning electron microscopy imaging was done on a 200x150μm area …

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Characterizing Hmx/Ap Cocrystal Propellant Through Planar Laser Induced Fluorescence, Seth M. Nielsen, Michael S. Powell, Steven F. Son Aug 2016

Characterizing Hmx/Ap Cocrystal Propellant Through Planar Laser Induced Fluorescence, Seth M. Nielsen, Michael S. Powell, Steven F. Son

The Summer Undergraduate Research Fellowship (SURF) Symposium

Energetic cocrystals, or energetic materials that consist of two or more components that form a unique crystalline structure with unique properties, are currently being investigated as a possible method for decreasing the sensitivity of high energy density explosives for use in powerful solid composite propellants. Fuels more powerful than those in current use have not been practical because of their increased safety hazard due to higher sensitivity to being ignited. This has been one of the barriers that has prevented solid composite propellants from seeing significant improvements in performance. This study is an attempt to characterize a cocrystal of HMX …

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Energy Transfer In Cdse Nanoplatelet Superlattices, Kelly Wang, Jordan Snaider, Libai Huang Aug 2016

Energy Transfer In Cdse Nanoplatelet Superlattices, Kelly Wang, Jordan Snaider, Libai Huang

The Summer Undergraduate Research Fellowship (SURF) Symposium

Two-dimension CdSe semiconductor nanoplatelets (NPLs) exhibit unique, highly desirable optical and electronic properties, such as large absorption crossection and bright emission. Fӧrster resonance energy transfer (FRET) between NPLs is responsible for the utility of these NPLs in fields such as lasing, lighting, solar energy, and sensing. Here we study energy transfer processes in NPL superlattices using photoluminescence (PL) and time resolved PL (TRPL) spectroscopic methods. Information on the effect of thickness of NPL is obtained through correlating PL and TRPL spectra of CdSe superlattices with AFM measurements. PL spectrum showed narrow fluorescence and absorption peaks at room temperature corresponding to …

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A Compact System For Photon Counting Based On Silicon Photomultiplier, Youngwoo Cho, Youngkee Jung, Euiwon Bae Aug 2016

A Compact System For Photon Counting Based On Silicon Photomultiplier, Youngwoo Cho, Youngkee Jung, Euiwon Bae

The Summer Undergraduate Research Fellowship (SURF) Symposium

A compact and portable detection system is necessary to measure the amount of pollutant from environmental sample by detecting and quantifying the light emitted by bioluminescent reporters. This silicon photomultiplier based project is hoping to acquire even more accurate data at a far lower light level than previously developed smartphone based system. After pre-amplification and comparator, the signal is separated from the internal noise present in the overall circuit. Next, the microcontroller counts the number of pulses generated by the comparator in a set amount of time and transfers the data to the Bluetooth module for the smartphone to receive …

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