Engineering Commons^™

Shape Memory Alloy Capsule Micropump For Drug Delivery Applications, Youssef Mohamed Kotb

Theses and Dissertations

Implantable drug delivery devices have many benefits over traditional drug administration techniques and have attracted a lot of attention in recent years. By delivering the medication directly to the tissue, they enable the use of larger localized concentrations, enhancing the efficacy of the treatment. Passive-release drug delivery systems, one of the various ways to provide medication, are great inventions. However, they cannot dispense the medication on demand since they are nonprogrammable. Therefore, active actuators are more advantageous in delivery applications. Smart material actuators, however, have greatly increased in popularity for manufacturing wearable and implantable micropumps due to their high energy …

Physical Effects On The Worst-Case Delay Analysis And Signal Integrity Of Buses And Spirals, Mahmoud Mahany

Theses and Dissertations

Physical effects have a significant impact on the IC design which will be investigated in this thesis. Moving toward advanced technology nodes, magnetic effects become more dominant than capacitive effects. As the dimensions of the devices go down and the interconnect manipulates the circuit behavior more and more. Cross talking and voltage drops are affecting the design heavily, however - going to the full electromagnetic point of view - current return path (CRP) adds significant parasitics to the performance of the chip. Neglecting the CRP gives wrong intuition and simulation of the designs, especially that the environment and surroundings can …

Study Of Accidental Sliding-Mode Control, April Mary Miller

Theses and Dissertations

The objective of this paper is to examine the Quanser SRV-02 motor servo for the presence of an accidental sliding mode. The SRV-02 is used by undergraduate students to learn basic concepts in controls engineering and will display unexpected sliding mode behavior when its in the “out of box” configuration. To gain a strong background understanding in characteristics of sliding mode, a review of literature on sliding-mode control and sliding mode behavior is completed. Next, a theoretical analysis of the SRV-02 motor servo during the sliding mode is developed. An effort is made to find a Lyapunov function that proves …

Improved Methodology For Conducted Emi Assessment Of Power Electronics And Line Impedance Measurement, Mark Anthony Didat

Theses and Dissertations

Electromagnetic Interference (EMI), primarily common mode (CM), is problematic in a wide range of electronic circuits due to its propensity to radiate, particularly in high power applications. It is routine for much effort and resources to be dedicated to its characterization and reduction as EMI compliance is a requirement for most electronic systems and devices, including power electronics. Many well-known factors contribute to a system’s EMI performance including intentional coupling from system components as well as unintentional coupling from parasitics. Sources of intentional coupling may include Y-capacitors intended to mitigate EMI as part of a filter. Unintentional coupling is more …

Use Of Digital Twins To Mitigate Communication Failures In Microgrids, Andrew Eggebeen

Theses and Dissertations

This work investigates digital twin (DT) applications for electric power system (EPS) resilience. A novel DT architecture is proposed consisting of a physical twin, a virtual twin, an intelligent agent, and data communications. Requirements for the virtual twin are identified. Guidelines are provided for generating, capturing, and storing data to train the intelligent agent. The relationship between the DT development process and an existing controller hardware-in-the-loop (CHIL) process is discussed. To demonstrate the proposed DT architecture and development process, a DT for a battery energy storage system (BESS) is created based on the simulation of an industrial nanogrid. The creation …

A Design Strategy To Improve Machine Learning Resiliency Of Physically Unclonable Functions Using Modulus Process, Yuqiu Jiang

Theses and Dissertations

Physically unclonable functions (PUFs) are hardware security primitives that utilize non-reproducible manufacturing variations to provide device-specific challenge-response pairs (CRPs). Such primitives are desirable for applications such as communication and intellectual property protection. PUFs have been gaining considerable interest from both the academic and industrial communities because of their simplicity and stability. However, many recent studies have exposed PUFs to machine-learning (ML) modeling attacks. To improve the resilience of a system to general ML attacks instead of a specific ML technique, a common solution is to improve the complexity of the system. Structures, such as XOR-PUFs, can significantly increase the nonlinearity …

Gpu Based Monte Carlo Estimation Of Eddy Current Losses In Electromagnetic Coil-Core System, Adwaith Ravichandran

Theses and Dissertations

A novel parallelizable probabilistic approach to model eddy currents in AC electromagnets is presented in this research. Consequently, power loss associated with the formation of these eddy currents is estimated and validated using experimental data. Furthermore, predicting the effect of ferromagnetic alternating field enhancement on power loss in the source excitation winding has been an active area of research. Unlike a stationary field, an alternating sinusoidal field diffuses partially into the ferromagnetic material leading to a predictably sub-optimal field enhancement. To model these physics, finite element techniques employ nonlinear iterative solvers which are time consuming. A novel method is developed …

Project Thetis: A Low-Cost, Low-Profile Inertial Data Logger, Braidan Duffy

Theses and Dissertations

This thesis details the design, testing, calibration, and verification of a nine degree of freedom inertial measurement data logger for use with floating bodies. The instrument was conceived to address limitations of equipment used in classes within the Ocean Engineering department at Florida Institute of Technology. By meeting with several stakeholders and end users, a series of stakeholder requirements, capabilities, and component-level requirements were de- veloped that informed the design constraints. There were several hardware iterations of the board, culminating in Revision F5 which was extensively tested and proven. The design was inspected after testing concluded to determine which capabilities …

Characterization, Simulation, And Test Method For Image Artifacts Due To Phase Drift Of The Saw Filter In The Magnetic Resonance Receiver, Gabriel T. Jacobs

Theses and Dissertations

The receiver for a Magnetic Resonance (MR) scanner is responsible for capturing the precise frequency and phase of extremely low-power RF signals emanating from the human body; and consequentially must minimize unexpected phase drift in the received signal. One well-known source for temperature-dependent phase drift in RF electronics is the Surface Acoustic Wave (SAW) filter. In this work, the phase drift due to temperature changes in the SAW filter of an MR receiver was evaluated for its potential effects on image quality using several image quality metrics. A lab bench method was developed to playback MR images using typical lab-equipment …

Ultra Fast Dc Switch, Ian A. Buck

Theses and Dissertations

With advancements in power electronics, DC power systems are a strong contender forfuture power system and shipboard application studies. However, to ensure proper DC power systems, protection engineers must develop different DC protection schemes to maintain proper system protection levels. The critical issue behind developing DC protection devices is that the signal never crosses zero naturally, as in AC circuit breakers and AC disconnect switches. There is also a necessity for galvanic isolation in the DC protection system. A method developed is pairing a mechanical commercial-off-the-shelf vacuum interrupter, a Thomson coil actuator, and a current commutating drive circuit (CCDC). The …

Stochastic Worst-Case Test Vectors For Asic Devices In Single Event Environment, Mostafa Hemeda

Theses and Dissertations

Charged particles and energetic particles can impact the integrated circuit, referred to as single event effects (SEE). Nuclear reactors and space radiation can produce these particles. These effects can negatively affect the reliability and performance of electronics. When SEE occurs, a transient current is created, which can cause electronic devices to have incorrect outputs and ultimately fail. As a result, ensuring the reliability of ASIC circuits is a significant concern.

This thesis discusses the different fault types, then discuss the soft error and, in particular, the Single Event Transient (SET) and its causes and models. Then, this thesis proposes a …

Design Of High-Power Ultra-High-Speed Permanent Magnet Machine, Md Khurshedul Islam

Theses and Dissertations

The demand for ultra-high-speed machines (UHSM) is rapidly growing in high-tech industries due to their attractive features. A-mechanically-based-antenna (AMEBA) system is another emerging application of UHSM. It enables portable wireless communication in the radio frequency (RF)-denied environment, which was not possible until recently. The AMEBA system requires a high-power (HP) UHSM for its effective communication performance. However, at the expected rotational speed range of 0.5 to 1 million rpm, the power level of UHSM is limited, and no research effort has succeeded to improve the power level of UHSM.

The design of HP-UHSM is highly iterative, and …

Relaxing Dc Capacitor Voltage Of Power Electronic Converters To Enhance Their Stability Margins, Ali Zakerian

Theses and Dissertations

Recently, due to the increasing adoption of distributed energy resource (DER) technologies including battery energy storage (BES) and electric vehicle (EV) systems, bidirectional power converters are becoming more popular. These converters are broadly utilized as interface devices and provide a bidirectional power flow in applications where the primary power supply can both supply and receive energy. A dc capacitor, called the dc-link, is an important component of such bidirectional converters. For a wide range of applications, the converter is required to control the dc-link voltage. Commonly, a proportional-integrating (PI) controller is used by the dc capacitor voltage controller to generate …

Allocation And Compilation Methodology For Modular Power Electronic Equipment Metamodels, William J. Koebel

Theses and Dissertations

With the ongoing electrification of Navy vessels motivated by increased power demands, evolving operating environments, and more stringent pollution policies, modular distribution networks have been proposed to introduce survivability, affordability, and resiliency into future ship designs. A virtual prototyping process (VPP) has been introduced to produce scalable metamodels for the Leading Edge Architecture for Prototyping Systems (LEAPS) database that enables development of modular distribution networks on the U.S. Navy’s Smart Ship System Design (S3D) design platform. This work proposes an allocation and compilation methodology for use in the VPP that modularizes enabling technologies for integration into a modular distribution network …

Cellulose Nanocrystal Dielectric Elastomers, David Frailey

Theses and Dissertations

Optical devices, such as filters and sensors, have numerous advantages including compactness in size and immunity from electromagnetic interference. The fabrication of optical devices often requires precision and complicated processing, resulting in expensive and delicate components. Cellulose nanocrystals (CNCs) are biomaterials that can self-assemble into liquid crystals, similar to those used in electronic displays. This material can function as an optical grating by reflecting/transmitting circularly polarized light at certain wavelengths and viewing angles. Since gratings are building blocks of optical systems, like lasers and lidars, their fabrication at low costs will enable the further proliferation of optical technologies. Furthermore, if …

Applications Of Surface Discharge Modeling, Simulation And Testing To Electrical Insulation Systems, Skyler Schwartz

Theses and Dissertations

Advances in power electronics and the increasing demand for highly power dense power distributionsystems have increased the demands for electrical insulation systems. A critical challenge in insulation system design is the prevention and mitigation of partial discharge which drives premature aging and failure of electrical assets. This work applies and validates a recently proposed model for surface discharge applied to the case of a laminated bus bar. The results from the modeling and testing shows the traditional concept of creepage, while essential for preventing a flashover events provides little insight into surface discharge. The approach to characterize the laminated bus …

A Distributed Control System For Microgrids With Wide Dynamic Response Components, Hadi Akbari Haghighat

Theses and Dissertations

Inverters play a vital part in microgrid operations and control, boosting system flexibility and efficiency. However, their limited physical inertia makes them vulnerable to network-induced oscillations. Research is primarily focused on addressing this by adding inertia to the inverter side. Earlier analysis of stand-alone microgrids utilized pure inverter-based systems with droop control for power sharing among units, and generators were responsible for voltage and frequency control. Inverter-based systems without communication latency have been studied. However, these studies don't provide a complete dynamic model of microgrids, especially for hybrid microgrids. In this study, a systematic approach is presented to model a …

Design Of A Miniaturized Cubesat Tt&C Patch Antenna, Thomas A. Butterick

Theses and Dissertations

This effort explored the design of miniaturized rectangular microstrip patch antennas for application as a telemetry, tracking, and control (TT&C) on a CubeSat. The motivation for this research was the Grissom-P CubeSat mission planned by AFIT. The TT&C antenna selected for the mission exceeded the allotted size by over a factor of two. The studies performed included analyses of simply reducing aperture size, altering substrate permittivity, and layered approaches to antenna miniaturization. The primary approach to miniaturization was based on a virtually shorted patch antenna. Other approaches included an edge-shorted, slotted patch and the use of corner truncations for improved …

Effects Of Calibration Errors On Dropped-Channel Polarimetric Synthetic Aperture Radar, Jacob C. Morrison

Theses and Dissertations

Compressed Sensing (CS) is a mathematical technique that can be applied to sparse data sets to allow for sub-Nyquist sampling. DCPCS is a CS technique that recovers the signal from unmeasured polarisation channels due to antenna crosstalk coupling the information onto the remaining channels. DCPCS reduces data storage/transmission and receiver hardware requirements. This thesis examines the robustness of DCPCS to calibration errors on the antenna crosstalk matrix. Although the antenna design problem is relaxed to a large region of acceptable crosstalk values, very accurate calibration may be required in a monostatic radar. This thesis also looks at the importance of …

Robust Feature Matching For Visual-Based Aerial Navigation Using Registered Imagery, Luis Montenegro

Theses and Dissertations

This work leverages the SIFT detector along with known robust feature matching techniques for vision-aided sUAS navigation solutions. The proposed algorithm focuses on a sufficient number of features extracted, their quality and their distribution.

Classifying Open-Air Target Measurements Using Simulation-Trained Convolutional Neural Networks, Matthew M. Rofrano

Theses and Dissertations

No abstract provided.

Comparison Of Federated Kalman Filter And Autonomous Resilient Management Of All-Source Sensors (Armas) Framework For Fault Detection And Exclusion, Flavio Fernandes

Theses and Dissertations

In recent times, there is a great demand for resilient and robust PNT solutions. Current navigation systems rely heavily on GNSS to provide this solution. This dependence is a major concern and therefore it is prudent to use additional aids to provide the best solution possible. However, traditional methods to address this need require a nontrivial number of Kalman filters to maintain a fault-free solution. The federated filter approach provides an attractive alternative to the current solutions. In this thesis, we examine the use of the federated filter design to address this need in today’s integrated navigation systems. We compared …

Detection And Identification Of Covert Devices Using Infrared And Stacked Optics Detection, Michael A. Reyneke

Theses and Dissertations

This work investigates stacked optics detection methodologies to successfully detect and identify observational systems with a cyber-physical sensing tool, ODIN (Observational Device Identification Network). ODIN successfully detected the presence of stacked optics and LiDAR systems using night-vision devices with a 96.32% average accuracy rating, both overt and covertly placed, with objective lens diameters ranging from 17 mm to 50 mm at distances between 1 m to 5 m with and without commonly employed anti-reflective countermeasures. ODIN provides a foundation for counter- measure capabilities of NIR devices and stacked optical systems in stationary environments. Additionally, a pilot study on smartphone LiDAR …

Wifi Sensing At The Edge Towards Scalable On-Device Wireless Sensing Systems, Steven M. Hernandez

Theses and Dissertations

WiFi sensing offers a powerful method for tracking physical activities using the radio-frequency signals already found throughout our homes and offices. This novel sensing modality offers continuous and non-intrusive activity tracking since sensing can be performed (i) without requiring wearable sensors, (ii) outside the line-of-sight, and even (iii) through the wall. Furthermore, WiFi has become a ubiquitous technology in our computers, our smartphones, and even in low-cost Internet of Things devices. In this work, we consider how the ubiquity of these low-cost WiFi devices offer an unparalleled opportunity for improving the scalability of wireless sensing systems. Thus far, WiFi sensing …

High Power, Medium Frequency, And Medium Voltage Transformer Design And Implementation, Ahmad El Shafei

Theses and Dissertations

Many industrial applications that require high-power and high-voltage DC-DC conversion are emerging. Space-borne and off-shore wind farms, fleet fast electric vehicle charging stations, large data centers, and smart distribution systems are among the applications. Solid State Transformer (SST) is a promising concept for addressing these emerging applications. It replaces the traditional Low Frequency Transformer (LFT) while offering many advanced features such as VAR compensation, voltage regulation, fault isolation, and DC connectivity. Many technical challenges related to high voltage stress, efficiency, reliability, protection, and insulation must be addressed before the technology is ready for commercial deployment. Among the major challenges in …

Modeling And Validation Of Common-Mode Emission In Silicon Carbide Based Voltage Source Converters, Tianchen Li

Theses and Dissertations

Electromagnetic compatibility (EMC) issues have become one of the most difficult challenges in power converter designs. With the invention of wide bandgap (WBG) power semiconductors such as silicon carbide (SiC) and gallium nitride (GaN) power MOSFETs, the power converter designs are provided with the potential to be significantly more power dense than older generation converters using silicone IGBTs. However, the majority of spectral contents of the switching waveforms are moved from the very-low-frequency (VLF, 3 kHz to 30 kHz) range to low-frequency and up to the very-high-frequency (VHF, 30 MHz to 300 MHz) range. Moreover, due to the design traits …

Multichannel Blind Deconvolution Of Circularly Polarized Imagery, Patrick B. Cunningham

Theses and Dissertations

Current methods can be used to recreate an expected Stokes polarization vector from measured light for characterization purposes. However, this only applies to three of the Stokes parameters, that is, the linear polarization components. Circular polarization is not currently being utilized for object characterization because the mathematical complexity is greater than for that of linear polarization. This research will analyze a way to expand existing algorithms to include circular polarization and enable the complete reconstruction of the Stokes vector from the measured light into a blind deconvolution algorithm for Stokes estimation and image reconstruction.

Nonreciprocal Surface Waves On Gyrotropic Interfaces, Alexander Martin Holmes

Theses and Dissertations

In this dissertation, the properties of highly nonreciprocal (unidirectional) surface waves guided along the interface between free-space and various 2D and 3D gyrotropic continua are investigated using analytic, numerical, and experimental methods. From a classical electromagnetics perspective, nonreciprocity in the dispersion of surface wave modes supported by the interface is achieved by breaking both time-reversal and space-inversion symmetries in the collective response of the waveguide, which consists of the two interfaced materials. More recently, however, a connection to momentum space topology via the bulk-edge correspondence principle has been made for gyrotropic continua, providing additional insights into the underlying physics that …

Applications Of Machine Learning In Medical Prognosis Using Electronic Medical Records, Farnaz Hajiahmadifoomani

Theses and Dissertations

Approximately 84 % of hospitals are adopting electronic medical records (EMR) In the United States. EMR is a vital resource to help clinicians diagnose the onset or predict the future condition of a specific disease. With machine learning advances, many research projects attempt to extract medically relevant and actionable data from massive EMR databases using machine learning algorithms. However, collecting patients' prognosis factors from Electronic EMR is challenging due to privacy, sensitivity, and confidentiality. In this study, we developed medical generative adversarial networks (GANs) to generate synthetic EMR prognosis factors using minimal information collected during routine care in specialized healthcare …

Nonreciprocal Electromagnetics Of Layered Media, Samaneh Pakniyat

Theses and Dissertations

In plasmonic systems, interaction of light and surface plasmons leads to excitation of surface plasmon polaritons (SPPs) carrying energy on the surface. In an isotropic plasmonic system, the SPPs optical response is reciprocal, which means that the forward and backward surface waves have identical propagation behaviors and SPPs refract when they encounter a discontinuity on the surface. In order to excite SPPs resilient to the surface disorders, the system reciprocity needs to be broken by different techniques such as applying an external magnetic bias. In this case, the plasmonic system becomes a gyrotropic medium. Recently, it has been shown that …