Engineering Commons^™

Foreword Special Section On Electrical Contacts, Ronald A. Coutu Jr., Ravi Mahajan

Electrical and Computer Engineering Faculty Research and Publications

Welcome to the Special Topics Section dedicated to the 2016 Holm Conference on Electrical Contacts. This special section contains eight high-quality papers that comprehensively describe the state of the art and potential future directions for topics of great interest to our readers. The Editor-in-Chief (EIC), in consultation with the other EICs, Associate Editors (AEs), and domain experts, selects the topics for the special sections, and a Guest Editor or AE (GE/AE), who is a leading expert in the technical area, then directs the solicitation and peer review of the papers. In cases where the GE/AE is also an author, the …

Rotation Of Two-Petal Laser Beams In The Near Field Of A Spiral Microaxicon, S. S. Stafeev, Liam O'Faolain, M. V. Kotlyar

Cappa Publications

Using a spiral microaxicon with the topological charge 2 and NA = 0.6 operating at a 532-nm wavelength and fabricated by electron-beam lithography, we experimentally demonstrate the rotation of a two-petal laser beam in the near field (several micrometers away from the axicon surface). The estimated rotation rate is 55 °/mm and linearly dependent on the on-axis distance, with the theoretical rotation rate being 53 °/mm. The experimentally measured rotation rate is found to be linear and coincident with the simulation results only on the on-axis segment from 1.5 to 3 mm. The experimentally measured rotation rate is 66 °/mm …

Minimum Required Length For Geotechnical Lateral Stability Of Rocksocketed Pile Shafts, Arash Khosravifar, Zia Zafir

Civil and Environmental Engineering Faculty Publications and Presentations

The original strong-rock (SR) p-y curves for rock-socketed shafts exhibit a brittle response where the post-peak resistance drops to approximately zero. This brittle response could result in a progressive failure of the rock p-y curves which, in turn, results in excessive pile lengths. This paper proposes a modification to the strong-rock (SR) p-y curves where the post-peak residual strength is equal to 20% of the ultimate resistance (0.2*pult). This residual resistance is proposed based on the assumption that the lateral resistance of cracked rock (after the peak point) should not be smaller than the lateral resistance of heavily weathered rock …

Modeling And Simulation Of Mass Flow Of Steel Plate/Slab During Hot Rolling, X. Wang, S. Ganguly, K. Chandrashekhara, Mario F. Buchely, Semen Naumovich Lekakh, David C. Van Aken, Ronald J. O'Malley, D. Bai, Y. Wang, T. Natarajan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The ability to predict mass flow behavior during hot rolling is essential to product quality. In this study, viscoplastic models of the steels from SSAB and U.S. Steel were developed based on experimental stress-strain curves. A three-dimensional nonlinear finite element model was built to simulate a reverse plate hot rolling and a hot strip rolling process. For plate rolling, a seven pass schedule was simulated. The plastic strain distributions during rolling were investigated. The results show that the surface of the plate has larger plastic strain than the center. In the case of hot strip rolling, the simulation predicts that …

New Algorithms For Compressed Sensing Of Mri: Wtwts, Dwts, Wdwts, Srivarna Settisara Janney

Master of Science in Computer Science Theses

Magnetic resonance imaging (MRI) is one of the most accurate imaging techniques that can be used to detect several diseases, where other imaging methodologies fail. MRI data takes a longer time to capture. This is a pain taking process for the patients to remain still while the data is being captured. This is also hard for the doctor as well because if the images are not captured correctly then it will lead to wrong diagnoses of illness that might put the patients lives in danger. Since long scanning time is one of most serious drawback of the MRI modality, reducing …

New Approaches For Memristive Logic Computations, Muayad Jaafar Aljafar

Dissertations and Theses

Over the past five decades, exponential advances in device integration in microelectronics for memory and computation applications have been observed. These advances are closely related to miniaturization in integrated circuit technologies. However, this miniaturization is reaching the physical limit (i.e., the end of Moore's Law). This miniaturization is also causing a dramatic problem of heat dissipation in integrated circuits. Additionally, approaching the physical limit of semiconductor devices in fabrication process increases the delay of moving data between computing and memory units hence decreasing the performance. The market requirements for faster computers with lower power consumption can be addressed by new …

Flexural Strength, Ductility, And Serviceability Of Beams That Contain High-Strength Steel Reinforcement And High-Grade Concrete, Anas Yosefani

Dissertations and Theses

Utilizing the higher capacity steel in design can provide additional advantages to the concrete construction industry including a reduction of congestion, improved concrete placement, reduction in the required reinforcement and cross sections which would lead to savings in materials, shipping, and placement costs. Using high-strength reinforcement is expected to impact the design provisions of ACI 318 code and other related codes.

The Applied Technology Council (ATC-115) report "Roadmap for the Use of High-Strength Reinforcement in Reinforced Concrete Design" has identified key design issues that are affected by the use of high-strength reinforcement. Also, ACI ITG-6, "Design Guide for the Use …

Musical Casual Creator For Easy Self-Expression, Louis Lin, Ian Santillano

Computer Science and Engineering Senior Theses

People with autism often struggle with the ability to communicate. As a result, many people with autism become frustrated in their attempts to express their thoughts and feelings fully. Current forms of music therapy are designed to improve the lives of patients with autism, but are inefficient at developing their communication skills. Our project is designed to help music therapy patients express themselves through the creation of music. A patient will be able to “write” a song through the power of his or her feelings. With our system, music therapy patients can actively drive the entire creative process and learn …

Conference Program, Millicent Sullivan, Josué Sznitman, Lola Eniola-Adefeso, Srivatsan Kidambi

Nanotechnology in Medicine II: Bridging Translational in vitro and in vivo Interfaces

No abstract provided.

From Holographic Video Monitors To Optogenetic Probes: How Advancements To Leaky-Mode Modulator Technology Are Saving The World, Stephen Dalton Mclaughlin

Theses and Dissertations

The research presented in this dissertation focuses on improvements made to lithium niobate leaky-mode modulators for both holographic video and optogenetic applications. The specific improvements found herein are: (1) characterization of leaky-mode modulators to decrease driver bandwidth to match that of commodity graphics processing units, (2) the implementation of surface relief gratings as input couplers to replace rutile prism coupling, (3) the addition of backside surface relief gratings to create an orthogonal output face for the leaky-mode modulator, and (4) the creation of superimposed surface relief gratings in lithium niobate to enable multiple wavelength coupling at a single input angle. …

Laser Vaporization And Controlled Condensation (Lvcc) Of Graphene Supported Pd/Fe3o4 Nanoparticles As An Efficient Magnetic Catalysts For Suzuki Cross – Coupling, Hany A. Elazab Dr

Chemical Engineering

Herein, a reproducible, reliable, and efficient method was reported for the synthesis of palladium nanoparticles dispersed on a composite of Fe3O4 and graphene (Pd-Fe3O4/G) as a highly efficient active catalyst for being used in Suzuki cross–coupling reactions. Graphene supported Pd/Fe3O4 nanoparticles (Pd-Fe3O4/G) exhibit a remarkable catalytic performance towards Suzuki coupling reactions. Moreover, the prepared catalyst could be recycled for up to three times with high catalytic activity. The catalyst was prepared using LVCC synthesis; the prepared catalyst is highly magnetic which provides a platform to facilitate the separation process of the catalyst through applying an external magnetic field using a …

Advanced Stress Analysis, Benjamin Liaw

Open Educational Resources

No abstract provided.

Controllable Internal Mixing In Coalescing Droplets Induced By The Solutal Marangoni Convection Of Surfactants With Distinct Headgroup Architectures, Jerome J. Nash, Patrick T. Spicer, Kendra Erk

School of Materials Engineering Faculty Publications

Through several complementary experiments, an investigation of the bulk and interfacial flows that emerged during the coalescence of two water-in-oil droplets with asymmetric compositional properties was performed. By adding surfactant to one of the coalescing droplets and leaving the other surfactant-free, a strong interfacial tension gradient (i.e., solutal Marangoni) driving energy between the merging droplets generated pronounced internal mixing. The contributions of two distinct types of surfactant, anionic ammonium lauryl sulfate (ALS) and cationic cetyltrimethylammonium bromide (CTAB) on the rate of coalescence bridge expansion and on the generation of opposing flows during coalescence were investigated. All coalescence experiments supported the …

College Of Engineering News, Georgia Southern University

College of Engineering & Computing: News & Publications (2010-2023)

• Three GS Students Win WIT Scholarships

Wind Energy And Wind-Energy-Inspired Turbulent Wakes: Modulation Of Structures, Mechanisms And Flow Regimes, Elizabeth H. Camp

Dissertations and Theses

The interaction of turbulent wakes with one another and with the adjacent fluid directly impacts the generation of electricity in wind turbine arrays. Computational modeling is well suited to the repeated iterations of data generation that may be required to inform understanding of the function of wind farms as well as to develop control schemes for plant function. In order to perform such computational studies, a simplified model of the turbine must be implemented. One of the most computationally efficient parametrizations of the blade utilizes a stationary disk which has a prescribed drag and produces a wake. However, since accurate …

Framework Integrating Climate Model, Hydrology, And Water Footprint To Measure The Impact Of Climate Change On Water Scarcity In Lesotho, Africa, John W. Pryor

USF Tampa Graduate Theses and Dissertations

Water scarcity is a problem that will be exacerbated by climate change. Being able to model the effect of climate change on water scarcity is important to effectively plan the use of future water resources. This research integrated the Soil and Water Assessment Tool (SWAT), climate model, and water footprint analysis to measure the impact of climate change on future water scarcity. This was achieved through two objectives. The first objective was to create a modeling framework that links the output from climate model to SWAT and combined streamflow outputs from SWAT with water footprint analysis to measure how climate …

Influence Of Silica Nanoparticle Density And Flow Conditions On Sedimentation, Cell Uptake, And Cytotoxicity, Mostafa Yazdimamaghani, Zachary B. Barber, Seyyed Pouya Hadipour Moghaddam, Hamidreza Ghandehari

Chemical and Biochemical Engineering Faculty Research & Creative Works

Careful evaluation of the toxicological response of engineered nanomaterials (ENMs) as a function of physicochemical properties can aid in the design of safe platforms for biomedical applications including drug delivery. Typically, in vitro ENM cytotoxicity assessments are performed under conventional static cell culture conditions. However, such conditions do not take into account the sedimentation rate of ENMs. Herein, we synthesized four types of similar size silica nanoparticles (SNPs) with modified surface roughness, charge, and density and characterized their cytotoxicity under static and dynamic conditions. Influence of particle density on sedimentation and diffusion velocities were studied by comparing solid dense silica …

3d Numerical Study Of Multiphase Counter-Current Flow Within A Packed Bed For Post Combustion Carbon Dioxide Capture, Li Yang, Fang Liu, Zhengchang Song, Kunlei Liu, Kozo Saito

Mechanical Engineering Faculty Publications

The hydrodynamics within counter-current flow packed beds is of vital importance to provide insight into the design and operational parameters that may impact reactor and reaction efficiencies in processes used for post combustion CO₂ capture. However, the multiphase counter-current flows in random packing used in these processes are complicated to visualize. Hence, this work aimed at developing a computational fluid dynamics (CFD) model to study more precisely the complex details of flow inside a packed bed. The simulation results clearly demonstrated the development of, and changes in, liquid distributions, wetted areas, and film thickness under various gas and liquid …

Performance Comparison Of Phase Change Materials And Metal-Insulator Transition Materials For Direct Current And Radio Frequency Switching Applications, Protap Mahanta, Mohiuddin Munna, Ronald A. Coutu Jr.

Electrical and Computer Engineering Faculty Research and Publications

Advanced understanding of the physics makes phase change materials (PCM) and metal-insulator transition (MIT) materials great candidates for direct current (DC) and radio frequency (RF) switching applications. In the literature, germanium telluride (GeTe), a PCM, and vanadium dioxide (VO₂), an MIT material have been widely investigated for DC and RF switching applications due to their remarkable contrast in their OFF/ON state resistivity values. In this review, innovations in design, fabrication, and characterization associated with these PCM and MIT material-based RF switches, have been highlighted and critically reviewed from the early stage to the most recent works. We initially …

Rheological Behavior And Sensitivity Of Wood-Derived Bio-Oil Modified Asphalt Binders, Junfeng Gao, Hainian Wang, Zhanping You, Mohd Rosli Mohd Hasan, Yong Lei, Muhammad Irfan

Michigan Tech Publications, Part 1

The demand for bituminous materials is continuously growing; crude oil-based asphalt binders are non-renewable, and are facing rapid depletion. With the increase of petroleum-based asphalt prices, seeking an alternative, renewable material such as bio-asphalt has become a hot research topic. However, shortcomings in this research area have been identified, notably concerning the high-temperature performance of bio-asphalt at present. This research aims to comprehensively apply conventional tests to, and study the rheological behavior of, the high-temperature performances of bio-asphalt binders, i.e., by temperature and frequency sweeps, using a dynamic shear rheometer (DSR). It will also assess the chemical functional groups of …

Towards Optimal Concolic Testing, Xinyu Wang, Jun Sun, Zhenbang Chen, Peixin Zhang, Jingyi Wang, Yun Lin

Research Collection School Of Computing and Information Systems

Concolic testing integrates concrete execution (e.g., random testing) and symbolic execution for test case generation. It is shown to be more cost-effective than random testing or symbolic execution sometimes. A concolic testing strategy is a function which decides when to apply random testing or symbolic execution, and if it is the latter case, which program path to symbolically execute. Many heuristics-based strategies have been proposed. It is still an open problem what is the optimal concolic testing strategy. In this work, we make two contributions towards solving this problem. First, we show the optimal strategy can be defined based on …

Design And Characterization Of Chiral Elastic Metamaterials, Sheng Sang

Theses and Dissertations

Metamaterial are materials engineered to have more than one property that cannot be observed in nature. Commonly, they are made from assemblies of multiple elements fashioned from composite materials such as metals or plastics. Due to its diverse application such as elastic wave cloaking, focusing and absorbing, elastic metamaterial has been the subject of intense experimental research and theoretical work in the past decades. Despite this large-scale effort, designs of the unit cell of the periodic structure for achieving negative elastic moduli are still needed. In this thesis, we first studied the wave phenomenon in lattice structure and materials with …

Robust Pose Estimation Of A Robotic Navigation Aid For The Visually Impaired By Multimodal Data Fusion, He Zhang

Theses and Dissertations

For a visually impaired individual, it is a challenging task for him/her to plan and follow a path towards the destination. This task is referred to as wayfinding. In this paper, the functions of wayfinding are defined as localization (aka pose estimation) in an indoor environment and finding a way to get to the destination by using the location information. To address this issue, vision-based navigation systems that use a camera for pose estimation have been intensively studied. Several vision-based robotic navigation aids (RNAs) for the visually impaired have been developed. However, these RNAs are not reliable enough to assist …

Regulation Of Cellular Patterning Through The Extracellular Matrix, Lewis Scott, Lauren Griggs, Vani Narayanan, Daniel Conway Phd, Seth H. Weinberg Phd, Christopher Lemmon Phd

Biology and Medicine Through Mathematics Conference

No abstract provided.

Ccfss Special Edition Technical Bulletin Summer 2018, Wei-Wen Yu Center For Cold-Formed Steel Structures

CCFSS Technical Bulletins (1993 - 2020)

No abstract provided.

Preparation And Characterization Of Eva/Cort Microparticles For Rattlesnake Endocrinology Studies, Alexander C. Pauer

Materials Engineering

No abstract provided.

In Situ Sem Solidification Study Of Ga And Egain: A Characterization Technique For Monitoring The Microstructural Evolution Of Liquid Metals, Jeremy Geovann Del Aguila

Materials Engineering

Scanning electron microscopy (SEM) video recording is used to characterize the solidification of small volumes of 99.999% pure gallium (Ga) and eutectic gallium-indium (eGaIn) under a high vacuum environment. Specimen are superheated to 55℃ using a hot plate, cast into spherical droplets, and cooled in situ by means of a Peltier cooling stage. Special attention is given to the preparation of the specimen prior to viewing because of gallium and its alloys’ nature to form an oxide layer when melted and air cooled. The oxide acts as a skin that inhibits the observation of microstructural features during solidification. Heated samples …

Genetic Algorithm Amplifier Biasing System (Gaabs): Genetic Algorithm For Biasing On Differential Analog Amplifiers, Sean Whalen

Computer Engineering

Genetic Algorithm Amplifier Biasing System (GAABS) - Senior Project Analysis

Summary of Functional Requirements

This project integrates LTSpice with a python script that runs a genetic algorithm to bias a differential amplifier. The system biases the amplifier with 2 different voltages, the base voltage for the PNP BJTs of the active loads and a voltage controlling the current of the current sink. The project runs via a python script, gets data from LTSpice’s command line call, and iteratively runs until the system is biased to achieve the greatest gain on an arbitrary input voltage.

Primary Constraints

Some of the main …

An Evaluation Of Ultrasonic Shot Peening And Abrasive Flow Machining As Surface Finishing Processes For Selective Laser Melted 316l, Rhys Gilmore

Master's Theses

Additive Manufacturing, and specifically powder bed fusion processes, have advanced rapidly in recent years. Selective Laser Melting in particular has been adopted in a variety of industries from biomedical to aerospace because of its capability to produce complex components with numerous alloys, including stainless steels, nickel superalloys, and titanium alloys. Post-processing is required to treat or solve metallurgical issues such as porosity, residual stresses, and surface roughness. Because of the geometric complexity of SLM produced parts, the reduction of surface roughness with conventional processing has proven especially challenging. In this Thesis, two processes, abrasive flow machining and ultrasonic shot peening, …

Influence Of Macromolecular Crowding And Confinement On Enzyme Activity And Structure Under Native And Denaturing Conditions, Steven Long, Jeffrey Kunkel, Prashanth Asuri

Bioengineering

It is now well appreciated that both crowding and confinement influence enzyme structure and function due to excluded volume effects; however, the relative efficacies of these environments on protein fates remain unclear due to a lack of direct comparison studies. In this study, we explore the use of the biopolymer alginate to develop an in vitro platform to investigate the effects of both crowding and confinement on the behavior of two model enzymes - horseradish peroxidase and β-galactosidase. Alginate, in its solution phase, can be used as a crowding agent and, in its gel phase by crosslinking using divalent cations, …