Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 30 of 35

Full-Text Articles in Entire DC Network

Detection Of Nucleotides In Hydrated Ssdna Via 2-D H-Bn Nanopore With Ionic-Liquid/Salt-Water Interface, Jungsoo Lee Dec 2020

Detection Of Nucleotides In Hydrated Ssdna Via 2-D H-Bn Nanopore With Ionic-Liquid/Salt-Water Interface, Jungsoo Lee

Multidisciplinary Studies Theses and Dissertations

Accomplishing slow translocation speed with high sensitivity has been the greatest mission for solid-state nanopore (SSN) to electrically detect nucleobases in single-stranded DNA (ssDNA). In this study, a method to detect nucleobases in ssDNA using a SSN is introduced by considerably slowing down the translocation speed and effectively increasing its sensitivity. The ultra-thin titanium dioxide (TiO2) coated hexagonal boron nitride (h-BN) nanopore was fabricated, along with an ionic-liquid [bmim][PF6]/2.0 M KCl aqueous (cis/trans) interfacial system, to increase both the spatial and the temporal resolutions. As the ssDNA molecules entered the nanopore, a …


Advanced Thermal Characterization And Temperature Control To Enable The Next Generation Of Micro-Electronic Technologies, Assaad El Helou Dec 2020

Advanced Thermal Characterization And Temperature Control To Enable The Next Generation Of Micro-Electronic Technologies, Assaad El Helou

Mechanical Engineering Research Theses and Dissertations

In the electronics world, self-heating is an inevitable by-product of electrical activation that has a major impact on device performance and reliability. Thermal technologies have been in constant development to effectively dissipate the generated heat and keep device operation temperatures within reliable limits. Moreover, thermal characterization technologies have been implemented to understand the thermal performance within microelectronic sys- tems, but not without facing experimental and numerical challenges. This work presents ad- vanced thermal investigations, both experimental and numerical, that are adapted and most suited for emerging micro-electronic technologies. Initially, the main experimental and numerical modeling challenges faced in the thermal …


Microparticle Propulsion For In Vivo Navigation, Louis Rogowski Dec 2020

Microparticle Propulsion For In Vivo Navigation, Louis Rogowski

Mechanical Engineering Research Theses and Dissertations

Microscale propulsion impacts a diverse array of fields, with simplistic microrobots allowing for novel innovations in microscale surgery and drug delivery. Propulsion at the microscale is constrained by physics, with time-reversal and geometric symmetries limiting available propulsion mechanisms. However, certain fluid environments and surface coatings allow for the propulsion of microparticles through externally applied magnetic fields. Presented here is a detailed analysis of microparticles propelling using spontaneous symmetry breaking, flagella surface coatings, and multi-modal actuation mechanisms. Spontaneous symmetry breaking in nonlinearly viscoelastic fluids is presented for the first time in literature, with two equal and opposite propulsion states existing along …


Mechanical Engineering News, Georgia Southern University Dec 2020

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering News (2013-2023)

  • Engineering Design Conference Held Virtually


Aerosol Jet Printed Capacitive Strain Gauge For Soft Structural Materials, Kiyo T. Fujimoto, Jennifer K. Watkins, Timothy Phero, Takoda Bingham, Kshama Lakshmi Ranganatha, Benjamin C. Johnson, Zhangxian Deng, Brian Jaques, David Estrada Nov 2020

Aerosol Jet Printed Capacitive Strain Gauge For Soft Structural Materials, Kiyo T. Fujimoto, Jennifer K. Watkins, Timothy Phero, Takoda Bingham, Kshama Lakshmi Ranganatha, Benjamin C. Johnson, Zhangxian Deng, Brian Jaques, David Estrada

Materials Science and Engineering Faculty Publications and Presentations

Soft structural textiles, or softgoods, are used within the space industry for inflatable habitats, parachutes and decelerator systems. Evaluating the safety and structural integrity of these systems occurs through structural health monitoring systems (SHM), which integrate non-invasive/non-destructive testing methods to detect, diagnose, and locate damage. Strain/load monitoring of these systems is limited while utilizing traditional strain gauges as these gauges are typically stiff, operate at low temperatures, and fail when subjected to high strain that is a result of high loading classifying them as unsuitable for SHM of soft structural textiles. For this work, a capacitance based strain gauge (CSG) …


High-Performance Flexible Bismuth Telluride Thin Film From Solution Processed Colloidal Nanoplates, Madhusudan Kongara, Tony Varghese, Karthik Chinnathambi, Jesse Schimpf, Josh Eixenberger, Paul H. Davis, Yaqiao Wu, David Estrada Nov 2020

High-Performance Flexible Bismuth Telluride Thin Film From Solution Processed Colloidal Nanoplates, Madhusudan Kongara, Tony Varghese, Karthik Chinnathambi, Jesse Schimpf, Josh Eixenberger, Paul H. Davis, Yaqiao Wu, David Estrada

Materials Science and Engineering Faculty Publications and Presentations

Thermoelectric generators are an environmentally friendly and reliable solid‐state energy conversion technology. Flexible and low‐cost thermoelectric generators are especially suited to power flexible electronics and sensors using body heat or other ambient heat sources. Bismuth telluride (Bi2Te3) based thermoelectric materials exhibit their best performance near room temperature making them an ideal candidate to power wearable electronics and sensors using body heat. In this report, Bi2Te3 thin films are deposited on a flexible polyimide substrate using low‐cost and scalable manufacturing methods. The synthesized Bi2Te3 nanocrystals have a thickness of 35 ± …


Modeling, Simulation, And Testing Of Sweeping Convection, Amir Kiaee Oct 2020

Modeling, Simulation, And Testing Of Sweeping Convection, Amir Kiaee

Mechanical Engineering Research Theses and Dissertations

In this study, the new convection heat transfer concept of sweeping convection, using large particles flowing with a fluid in a channel, is considered. This novel concept is inspired by the gas exchange process in alveolar capillaries, where red blood cells (RBCs) flow with blood plasma, yielding very high gas transfer efficiency. An important characteristic of alveolar capillary blood flow, believed to be related to the high efficiency of the lungs, is the snug fitting of the RBCs into the capillaries. This tight fitting sets the RBCs (particles) acting like pistons as they flow downstream with the plasma (fluid), facilitating …


A Cathode Support Structure For Use In A Magnetron Oscillator Experiment, Daylon Black, Ryan Harper, Patrick Ward, Jacob Davlin, Omar Bentancourt, Donald Plumlee, Jim Browning Sep 2020

A Cathode Support Structure For Use In A Magnetron Oscillator Experiment, Daylon Black, Ryan Harper, Patrick Ward, Jacob Davlin, Omar Bentancourt, Donald Plumlee, Jim Browning

Electrical and Computer Engineering Faculty Publications and Presentations

A Low Temperature Cofired Ceramic (LTCC) material system has been used to develop a protype field emission cathode structure for use in an experimental magnetron oscillator. The structure is designed for used with 30 Gated Field Emission Array (GFEA) die electrically connected through silver metal traces and electrical vias. To approximate a cylinder, the cathode structure (48 mm long and 13.7 mm in diameter) is comprised of 10 faceted plates which cover the GFEA dies. Slits in the facet plates allow electron injection. The GFEA die (3 mm x 8 mm) are placed in axial columns of 3 and spaced …


Mechanical Engineering News, Georgia Southern University Aug 2020

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering News (2013-2023)

  • Dr. Cesmeci Awarded DOE Grant


Mechanical Engineering News, Georgia Southern University Aug 2020

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering News (2013-2023)

  • Dr. M. Xu Receives Faculty Award from AIST


Mechanical Engineering News, Georgia Southern University Aug 2020

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering News (2013-2023)

  • Computer Lab Availability for Commuting Students


Wireless Wearable System For The Assessment Of Gait, Abdallah Jabr Aug 2020

Wireless Wearable System For The Assessment Of Gait, Abdallah Jabr

Mechanical Engineering Research Theses and Dissertations

This work investigates the development and use of a wireless wearable system for the assessment of gait. The system proposed consists of a sensor module that is attached to the foot. The sensor proposed is an inertial measurement unit, often abbreviated as IMU - a 9-axis System in Package (SiP) including a 3-axis accelerometer, a 3-axis gyroscope, and a 3-axis magnetometer, as well as a fusion engine for signal processing. While the focus of this work is on evaluating gait metrics, the performance of the proposed IMU in evaluating orientation is quantified. In doing this work, we try to address …


Homogenization Of Composite And Cellular Materials Incorporating Microstructure And Surface Energy Effects, Ahmad Gad Aug 2020

Homogenization Of Composite And Cellular Materials Incorporating Microstructure And Surface Energy Effects, Ahmad Gad

Mechanical Engineering Research Theses and Dissertations

In the last few decades, the popularity of composite and cellular materials has rapidly increased through their widespread applications in multiple engineering fields including aerospace, automotive, civil and biomedical. However, to a large extent, the success of their practical applications depends on our ability to predict their mechanical behavior by using high-fidelity mechanics models.

Micromechanical modeling of composite and cellular materials is a challenging task due to the heterogeneous nature of such materials and the interactions among various constituent phases at the microscopic level, which result in non-homogeneous deformation, strain and stress fields. Therefore, it is necessary to develop simple …


Work In Progress: Development Of A General Education First-Year Design Course, Courtney Hollar, Sondra M. Miller Jun 2020

Work In Progress: Development Of A General Education First-Year Design Course, Courtney Hollar, Sondra M. Miller

Civil Engineering Faculty Publications and Presentations

We discuss in this Work in Progress paper the development of a new first-year engineering course at Boise State University. ENGR 180 Communication in Design Thinking, was developed in order to emphasize the importance of communication throughout the design process. Communication with the client at the start of the design process occurs in order to understand the problem to be solved. The team and other stakeholders continuously communicate in order to work toward developing a prototype to solve the problem. The ability to effectively communicate is equally as important to the design of the final product. The development of ENGR …


Heavy Lift Drone, Sam Carhart, David Cooper, Luis Gaitan, Michael Kaliterna, Sami Lama, Paul Rogel-Herrera, Yuya Yabe Jun 2020

Heavy Lift Drone, Sam Carhart, David Cooper, Luis Gaitan, Michael Kaliterna, Sami Lama, Paul Rogel-Herrera, Yuya Yabe

Interdisciplinary Design Senior Theses

Despite the rapid rise in the number of drones in the past few years, there has been little work done to produce a drone that is optimized for the FAA' s 55 lb upper takeoff limit. This gap in the market is one that the Heavy Lift Drone (HLD) fills - a light-weight, higher payload capability, and inexpensive drone to be used in commercial applications - most notably irrigation monitoring. The HLD is a contra-rotating hexagonal configuration system featuring two levels of propellers that allow for larger propeller diameter and generate greater lift. After performing extensive finite element analyses and …


Adaptive Robotic Chassis (Arc), Darran Casey, Ryan Ku, Noah Kane Manuel, Isabella Morales, James Reimer, Lavelle Simmons Jun 2020

Adaptive Robotic Chassis (Arc), Darran Casey, Ryan Ku, Noah Kane Manuel, Isabella Morales, James Reimer, Lavelle Simmons

Interdisciplinary Design Senior Theses

The ARC is a width adjusting agricultural robot and accommodates auxiliary functions for supporting crop production and maintenance. Easily interchangeable payloads and components provide a modular solution to perform focused crop surveying functions with the potential for herbicide distribution, weeding, and harvesting while driving through varying crop rows. The potential auxiliary functions will be implemented by future teams with this year's effort being put toward finishing the physical chassis. The final product was successfully designed to weigh approximately 600 pounds targeting rolling speeds of0.90 fps to 2.30 fps with proof of concept shown in testing consisting of chain drive attached …


Application Of Optimal Switching Using Adaptive Dynamic Programming In Power Electronics, Ataollah Gogani Khiabani May 2020

Application Of Optimal Switching Using Adaptive Dynamic Programming In Power Electronics, Ataollah Gogani Khiabani

Mechanical Engineering Research Theses and Dissertations

In this dissertation, optimal switching in switched systems using adaptive dynamic programming (ADP) is presented. Two applications in power electronics, namely single-phase inverter control and permanent magnet synchronous motor (PMSM) control are studied using ADP. In both applications, the objective of the control problem is to design an optimal switching controller, which is also relatively robust to parameter uncertainties and disturbances in the system. An inverter is used to convert the direct current (DC) voltage to an alternating current (AC) voltage. The control scheme of the single-phase inverter uses a single function approximator, called critic, to evaluate the optimal cost …


Control And Locomotion Of Inertially And Magnetically Actuated Multi-Scale Robotic Systems, Ehab Al Khatib May 2020

Control And Locomotion Of Inertially And Magnetically Actuated Multi-Scale Robotic Systems, Ehab Al Khatib

Mechanical Engineering Research Theses and Dissertations

In this research, two actuation systems were introduced, inertial and magnetic actuation. In the inertial actuation, the robot used the transfer of momentum to navigate, and this momentum could be generated by spinning masses and wheels. Recent studies in our System Laboratory proved that a wide range of inertially actuated locomotion systems could be generated. This can be achieved by using a family tree approach, starting from a very simple system, and progressively evolving it to more complex ones. The motion diversity of these robots inspired us to extend their locomotion from a macro scale to millimeter and micro scales. …


Utilizing The Product Development Process To Bring An Idea From Concept To Production, Sydney Ferguson, Jackson Sneed May 2020

Utilizing The Product Development Process To Bring An Idea From Concept To Production, Sydney Ferguson, Jackson Sneed

Honors Theses

The purpose of this thesis is to document and discuss the five-stage product development process starting with defining a problem and resulting in manufacturing a final product for sale as it was implemented in the Portable Fire Pit Center for Manufacturing Excellence Senior Capstone Project. This project was carried out over the course of the Fall 2019 and Spring 2020 semesters by a team consisting of three Undergraduate Mechanical Engineering majors and two Undergraduate Accountancy majors. The ultimate goal of the project was to carry out a full production run of the Portable Fire Pit outputting fifteen units meeting retail …


Basil Leaf Automation, Andrew Soong, Chris Nelson, John Goldsberry, Kalle Suzuki, Nikolas Abenoja, Sherene Victor, Simon Liu Apr 2020

Basil Leaf Automation, Andrew Soong, Chris Nelson, John Goldsberry, Kalle Suzuki, Nikolas Abenoja, Sherene Victor, Simon Liu

Interdisciplinary Design Senior Theses

Recent population and wage increases have forced farmers to grow more food without a proportionate increase in work force. Automation is a key factor in reducing cost and increasing efficiency. In this paper, we explore our automation solution that utilizes position manipulation and vision processing to identify, pick up, and drop a leaf into a can. Two stepper motors and a linear actuator drove the three-dimensional actuation. Leaf and can recognition were accomplished through edge detection and machine learning algorithms. Testing proved subsystem-level functionality and proof of concept of a delicate autonomous pick-and-place robot.


Critical Point Identification In 3d Velocity Fields, Mohammadreza Zharfa Apr 2020

Critical Point Identification In 3d Velocity Fields, Mohammadreza Zharfa

Mechanical Engineering Research Theses and Dissertations

Classification of flow fields involving strong vortices such as those from bluff body wakes and animal locomotion can provide important insight to their hydrodynamic behavior. Previous work has successfully classified 2D flow fields based on critical points of the velocity field and the structure of an associated weighted graph using the critical points as vertices. The present work focuses on extension of this approach to 3D flows. To this end, we have used the Gauss-Bonnet theorem to find critical points and their indices in the 3D velocity vector field, which functions similarly to the Poincare-Bendixon theorem in 2D flow fields. …


Stability Analysis, Dynamic Modeling, And Kinematic Analysis Of Hydraulically Amplified Dielectric Elastomer Actuators And Robot Manipulators, Amir Hosein Zamanian Apr 2020

Stability Analysis, Dynamic Modeling, And Kinematic Analysis Of Hydraulically Amplified Dielectric Elastomer Actuators And Robot Manipulators, Amir Hosein Zamanian

Mechanical Engineering Research Theses and Dissertations

In this dissertation, we have proposed a new dielectric elastomer actuator design and model that couples electrostatics, fluid mechanics, linear and nonlinear elastic deformations. The internal hydraulic pressure can amplify the structural deformation generated by induced electrostatic forces (Maxwell pressure), given the name of this class of actuators, hydraulically amplified dielectric elastomer actuators (HADEAs).

First, we developed novel lumped-parameter models (LPMs) using linear and hyper-elastic material models and second compared the LPM results with finite element analysis in quasi-static simulations. We analytically expressed the conditions for the snap-through instability in the HADEA, which appears after exceeding a certain voltage applied …


Design Of A Greywater-Fed Hydroponics System, Alex Estrada, Katya Fairchok, Andrew Feldmeth, Andrew Jezak Apr 2020

Design Of A Greywater-Fed Hydroponics System, Alex Estrada, Katya Fairchok, Andrew Feldmeth, Andrew Jezak

Interdisciplinary Design Senior Theses

To combat issues of local water insecurity, a hydroponics system was designed in partnership with LEAP 5 High School in Jane Furse, South Africa. Climate change, increasing human population, and continued environmental degradation all threaten access to clean drinking water. Approximately seventy percent of all freshwater is used for agriculture globally, thus threatening food security especially in developing countries where access to water is potentially volatile. The hydroponics garden system utilizes sustainable materials, a self-monitoring temperature controls system, and greywater input, to act as an educational tool for students and significantly reduce freshwater use compared to traditional, in-ground agriculture. An …


Correlating In-Situ Monitoring Data With Internal Defects In Laser Powder Bed Fusion Additive Manufacturing, Andrew J. Harvey Jan 2020

Correlating In-Situ Monitoring Data With Internal Defects In Laser Powder Bed Fusion Additive Manufacturing, Andrew J. Harvey

Browse all Theses and Dissertations

The presence of defects within laser powder bed fusion (LPBF) parts can lead to reduced mechanical properties and life of components. Because of this, the ability to detect these defects within the parts is critical before the part is subject to its intended loading. Normally the parts are subjected to a quality analysis once they are completed however, this process is typically expensive and time consuming. A solution for these problems is to sense the creation of defects and pores in the parts in-situ, while the part is being fabricated. One proposed method of in-situ monitoring is visible spectroscopy to …


The Thermal And Mechanical Characteristics Of Lithiated Peo Lagp Composite Electrolytes, Jacob Michael Denney Jan 2020

The Thermal And Mechanical Characteristics Of Lithiated Peo Lagp Composite Electrolytes, Jacob Michael Denney

Browse all Theses and Dissertations

Lithium-ion batteries are part of a multibillion-dollar industry that strives to meet the demands for an increasingly advanced technological future. Flexible batteries can be easily adapted from emerging novel wearable electronics to electrical vehicles and advanced solar panels. Solid-state batteries can greatly reduce the risk of fire or leaking hazardous materials due to puncture. For the development of solid-state flexible lithium based batteries polymer-ceramic composites are attractive electrolyte candidates because of their combined properties, such as electrical, thermal and mechanical properties, that not only overcome limitations from the base materials but may also render some enhanced performances resulting from the …


Optimization Study Of A Combined Wind-Solar Farm For A Specified Demand, Venkat Siddhartha Rama Jan 2020

Optimization Study Of A Combined Wind-Solar Farm For A Specified Demand, Venkat Siddhartha Rama

Browse all Theses and Dissertations

At the present time, using wind and solar energy for producing electricity in the United States is becoming cost competitive. According to Lazard’s 2019 [36] levelized cost of energy (LCOE) analysis of a number of energy sources used for producing electricity in the United States, wind and solar are cheaper than natural gas and coal. While capital, maintenance, operation, and fuel costs are included in LCOE numbers, energy source intermittency is not. Intermittency is an important issue with wind and solar energy sources, but not with natural gas or coal energy sources. Combining wind and solar energy sources into one …


Adaptive Multi-Fidelity Modeling For Efficient Design Exploration Under Uncertainty, Atticus J. Beachy Jan 2020

Adaptive Multi-Fidelity Modeling For Efficient Design Exploration Under Uncertainty, Atticus J. Beachy

Browse all Theses and Dissertations

This thesis work introduces a novel multi-fidelity modeling framework, which is designed to address the practical challenges encountered in Aerospace vehicle design when 1) multiple low-fidelity models exist, 2) each low-fidelity model may only be correlated with the high-fidelity model in part of the design domain, and 3) models may contain noise or uncertainty. The proposed approach approximates a high-fidelity model by consolidating multiple low-fidelity models using the localized Galerkin formulation. Also, two adaptive sampling methods are developed to efficiently construct an accurate model. The first acquisition formulation, expected effectiveness, searches for the global optimum and is useful for modeling …


Developing Equivalent Solid Model For Lattice Cell Structure Using Numerical Approaches, Tahseen Abdulridha Ali Al-Wattar Jan 2020

Developing Equivalent Solid Model For Lattice Cell Structure Using Numerical Approaches, Tahseen Abdulridha Ali Al-Wattar

Browse all Theses and Dissertations

Lattice cell structures (LCS) are the engineered porous structures that are composed of periodic unit cells in three dimensions. Such structures have many scientific and engineering applications, such as in vessel gas technology, thermal systems, mechanical and aerospace structures, etc. for which lightweight, high strength, and energy absorption capabilities are essential properties. To have an optimized design, finite element analysis (FEA) based computational approach can be used for detailed analysis of such structures, sometime in full scale. However, developing a large-scale model for a lattice-based structure is computationally expensive. If an equivalent solid FE model can be developed using the …


Turbine Passage Vortex Response To Upstream Periodic Disturbances, Mitchell Lee Scott Jan 2020

Turbine Passage Vortex Response To Upstream Periodic Disturbances, Mitchell Lee Scott

Browse all Theses and Dissertations

Flow through the turbine section of gas turbine engines is inherently unsteady due to a variety of factors, such as the relative motion of rotors and stators. In low pressure turbines, periodic wake passing has been shown to impact boundary layer separation, blade surface pressure distribution, and loss generation. The effect of periodic disturbances on the endwall flow is less understood. Endwall flow in a low-pressure turbine occurs in the boundary layer region of the flow through the blade passage where the blade attaches to the hub in the turbine. The response of an endwall vortical structure, the passage vortex, …


Thermal Modeling Of Coordinated Multi-Beam Additive Manufacturing, Rachel Elizabeth Evans Jan 2020

Thermal Modeling Of Coordinated Multi-Beam Additive Manufacturing, Rachel Elizabeth Evans

Browse all Theses and Dissertations

In additive manufacturing (AM), it is necessary to know the influence of processing parameters in order to have better control over the microstructure and mechanical performance of the part. Laser powder bed fusion (LPBF) is a metal AM process in which thin layers of powdered material are selectively melted to create a three-dimensional structure. This manufacturing process is beneficial for many reasons; however, it is limited by the thermal solidification conditions achievable in the available processing parameter ranges for single-beam processing methods. Therefore, this work investigates the effect of multiple, coordinated heat sources, which are used to strategically modify the …