Engineering Commons^™

Novel Materials And Devices For Terahertz Detection And Emission For Sensing, Imaging And Communication, Naznin Akter

FIU Electronic Theses and Dissertations

Technical advancement is required to attain a high data transmission rate, which entails expanding beyond the currently available bandwidth and establishing a new standard for the highest data rates, which mandates a higher frequency range and larger bandwidth. The THz spectrum (0.1-10 THz) has been considered as an emerging next frontier for the future 5G and beyond technology. THz frequencies also offer unique characteristics, such as penetrating most dielectric materials like fabric, plastic, and leather, making them appealing for imaging and sensing applications. Therefore, employing a high-power room temperature, tunable THz emitters, and a high responsivity THz detector is essential. …

System Design And Control Optimization For Neurorehabilitation Exoskeleton, Rodrigo N. Ramon

FIU Electronic Theses and Dissertations

Neurorehabilitation is a comprehensive approach aimed at helping patients regain motor control after a neural injury, including spinal cord injury, stroke, or other ischemic events. Early-stage neurorehabilitation is particularly delicate due to voluntary muscular weakness and lack of motor control, presenting in the form of spasticity. Unfortunately, this period of elevated weakness is when most neural control improvement can be made through a phenomenon called brain plasticity. Early rehabilitation traditionally requires a human therapist due to the adaptive and dynamic interpretation of undesired neuromuscular events. While efforts have been made to develop devices to aid in neurorehabilitation, the considerations that …

Dual-Band Rf Receiver For Collocated Dsrc And 5g Millimeter-Wave Vehicle-To-Vehicle Communication, Sandhiya Reddy Govindarajulu

FIU Electronic Theses and Dissertations

In recent years, vehicle crashes have taken nearly 38,000 lives per year in the U.S., according to the National Highway Traffic Safety Administration (NHTSA). To improve the safety of the drivers, the Federal Communications Commission (FCC) has allocated the Dedicated Short Range Communications (DSRC) frequency spectrum, viz. 5.850-5.925 GHz band for vehicular communication. However, the limited bandwidth at the DSRC band provided an impetus to explore the millimeter-wave (mm-wave) spectrum that promises much higher data rates. Nevertheless, operating in the mm-wave spectrum comes with the expense of high path loss and attenuation due to rain.

To overcome the abovementioned problems, …

Transmission And Distribution Co-Simulation And Applications, Mohammad Asif Iqbal Khan

FIU Electronic Theses and Dissertations

As the penetration of flexible loads and distributed energy resources (DERs) increases in distribution networks, demand dispatch schemes need to consider the effects of large-scale load control on distribution grid reliability. Thus, we need demand dispatch schemes that actively ensure that distribution grid operational constraints are network-admissible and still deliver valuable market services. In this context, this work develops and evaluates the performance of a new network-admissible version of the device-driven demand dispatch scheme called Packetized Energy Management (PEM). Specifically, this work develops and investigates the live grid constraint-based coordinator and metrics for performance evaluation. The effects of grid measurements …

Thermal Aware Design Automation Of The Electronic Control System For Autonomous Vehicles, Ajinkya Bankar

FIU Electronic Theses and Dissertations

The autonomous vehicle (AV) technology, due to its tremendous social and economical benefits, is transforming the entire world in the coming decades. However, significant technical challenges still need to be overcome until AVs can be safely, reliably, and massively deployed. Temperature plays a key role in the safety and reliability of an AV, not only because a vehicle is subjected to extreme operating temperatures but also because the increasing computations demand more powerful IC chips, which can lead to higher operating temperature and large thermal gradient. In particular, as the underpinning technology for AV, artificial intelligence (AI) requires substantially increased …

A Machine Learning Framework For Identifying Molecular Biomarkers From Transcriptomic Cancer Data, Md Abdullah Al Mamun

FIU Electronic Theses and Dissertations

Cancer is a complex molecular process due to abnormal changes in the genome, such as mutation and copy number variation, and epigenetic aberrations such as dysregulations of long non-coding RNA (lncRNA). These abnormal changes are reflected in transcriptome by turning oncogenes on and tumor suppressor genes off, which are considered cancer biomarkers.

However, transcriptomic data is high dimensional, and finding the best subset of genes (features) related to causing cancer is computationally challenging and expensive. Thus, developing a feature selection framework to discover molecular biomarkers for cancer is critical.

Traditional approaches for biomarker discovery calculate the fold change for each …

Volitional Control Of Lower-Limb Prosthesis With Vision-Assisted Environmental Awareness, S M Shafiul Hasan

FIU Electronic Theses and Dissertations

Early and reliable prediction of user’s intention to change locomotion mode or speed is critical for a smooth and natural lower limb prosthesis. Meanwhile, incorporation of explicit environmental feedback can facilitate context aware intelligent prosthesis which allows seamless operation in a variety of gait demands. This dissertation introduces environmental awareness through computer vision and enables early and accurate prediction of intention to start, stop or change speeds while walking. Electromyography (EMG), Electroencephalography (EEG), Inertial Measurement Unit (IMU), and Ground Reaction Force (GRF) sensors were used to predict intention to start, stop or increase walking speed. Furthermore, it was investigated whether …

Parameter Estimation And Charge Control In Standalone And Grid-Tied Batteries, Asadullah Khalid

FIU Electronic Theses and Dissertations

Energy storage systems are the critical components enabling an electrified future ranging from electric vehicles (EVs) to microgrid (MG) applications. With the advancements in these applications, the operational dynamics of electrochemical energy storage such as Lithium-ion batteries need to be analyzed from the lifecycle impact, cybersecurity, balancing requirements, and prognostics perspectives. These operations enable the interconnected systems to be secure, efficient, and self-adaptive while reducing greenhouse emissions.

This research aims to develop threefold solutions. The first objective of this dissertation is to analyze lifecycle impact, quantify the interconnection requirements of battery energy storage systems, and evaluate cybersecurity frameworks for battery …

Tri-Level Hierarchical Coordinated Control Of A Largescale Electric Vehicle Charging In The Smart Grid, Tawfiq M. Aljohani

FIU Electronic Theses and Dissertations

Electric Vehicles (EVs) are considered one of humanity's greatest hopes to combat the climate change crises in light of their great potentials to reduce Greenhouse Gases (GHG) emissions from two main sources: the electric power industry and the fossil-based transportation sector. To help expedite the large-scale adoption of EVs on the roads, optimal solutions are needed to overcome the technical and operational barriers that face the electrical network. This is due to the introduction of significant load levels from EVs; a substantial number is expected during peak demand hours. This dissertation addresses the various interaction between different parts of the …

Impact-Based Analytics Of Cascaded False Data Injection Attacks On Smart Grids, Mohamadsaleh Jafari

FIU Electronic Theses and Dissertations

The composition of communication lines and bidirectional smart devices in smart grids makes them greatly vulnerable to cyber-attacks. False data injection attacks (FDIAs) are of the most widespread cyber-attacks severely affecting the performance of smart grids that need to be analyzed. In this context, we analyze the feasibility of launching FDIAs in power systems with high renewables leading to false relay operations (FRO). By modeling the frequency dynamics of power systems, formalizing the FRO attack as a constraint satisfaction problem, our case studies show that power grids with renewables are more susceptible to FRO attacks. Moreover, the results suggest that …

Machine Learning For Multiclass Classification And Prediction Of Alzheimer's Disease, Solale Tabarestani

FIU Electronic Theses and Dissertations

Alzheimer's disease (AD) is an irreversible neurodegenerative disorder and a common form of dementia. This research aims to develop machine learning algorithms that diagnose and predict the progression of AD from multimodal heterogonous biomarkers with a focus placed on the early diagnosis. To meet this goal, several machine learning-based methods with their unique characteristics for feature extraction and automated classification, prediction, and visualization have been developed to discern subtle progression trends and predict the trajectory of disease progression.

The methodology envisioned aims to enhance both the multiclass classification accuracy and prediction outcomes by effectively modeling the interplay between the multimodal …

Aptamer-Based Voltammetric Biosensing For The Detection Of Codeine And Fentanyl In Sweat And Saliva, Rosa Lashantez Cromartie

FIU Electronic Theses and Dissertations

Despite the many governmental and medicinal restrictions created to combat the opioid epidemic in the United States, opioid abuse and overdose rates continue to rise. The development of an aptamer-based voltammetric sensor and biosensor is described in this dissertation. The aim was to develop a low-cost, sensitive, and specific aptamer-based sensor for on-site, label-free determination of codeine and fentanyl in biological fluids. To do this, the surfaces of screen-printed carbon electrodes (SPCE) were modified with gold nanoparticles (AuNPs), followed by the addition of single-stranded DNA aptamers. These were covalently bound to the electrode surface. Operations of the sensors were collected …

Non-Invasive Techniques Towards Recovering Highly Secure Unclonable Cryptographic Keys And Detecting Counterfeit Memory Chips, Bashir Mohammad Sabquat Bahar Talukder

FIU Electronic Theses and Dissertations

Due to the ubiquitous presence of memory components in all electronic computing systems, memory-based signatures are considered low-cost alternatives to generate unique device identifiers (IDs) and cryptographic keys. On the one hand, this unique device ID can potentially be used to identify major types of device counterfeitings such as remarked, overproduced, and cloned. On the other hand, memory-based cryptographic keys are commercially used in many cryptographic applications such as securing software IP, encrypting key vault, anchoring device root of trust, and device authentication for could services. As memory components generate this signature in runtime rather than storing them in memory, …

Challenges Of Inductive Electric Vehicle Charging Systems In Both Stationary And Dynamic Modes, Hassan Jafari Mr

FIU Electronic Theses and Dissertations

Inductive power transfer as an emerging technology has become applicable in wide power ranges including Electric Vehicle, Electric Aircraft, wheelchair, cellphone, scooter and so on. Among them, inductive Electric Vehicle (EV) charging has gained great interest in the last decade due to many merits namely contactless technology, more convenience, full automotive charging process. However, inductive EV charging systems could bring about so many issues and concerns which are addressed in this dissertation. One of the critical challenges addressed in this dissertation is a virtual inertia based IPT controller to prevent the undesirable dynamics imposed by the EVs increasing number in …

Novel Attacks And Defenses For Enterprise Internet-Of-Things (E-Iot) Systems, Luis C. Puche Rondon

FIU Electronic Theses and Dissertations

This doctoral dissertation expands upon the field of Enterprise Internet-of-Things (E-IoT) systems, one of the most ubiquitous and under-researched fields of smart systems. E-IoT systems are specialty smart systems designed for sophisticated automation applications (e.g., multimedia control, security, lighting control). E-IoT systems are often closed source, costly, require certified installers, and are more robust for their specific applications. This dissertation begins with an analysis of the current E-IoT threat landscape and introduces three novel attacks and defenses under-studied software and protocols heavily linked to E-IoT systems. For each layer, we review the literature for the threats, attacks, and countermeasures. Based …

Digital Processing Of Magnetic, Angular-Rate And Gravity Signals For Human-Computer Interaction, Neeranut Ratchatanantakit

FIU Electronic Theses and Dissertations

This dissertation pursued the definition and evaluation of a processing approach for robust real-time orientation estimation of a miniature Magnetic, Angular-Rate, Gravity (MARG) module for use in a human-computer interaction system that also uses a 3-camera IR-video module for position estimation. The proposed algorithm introduces the novel idea of spatially mapping the level of trustworthiness of the magnetometer-based potential corrections to the orientation estimate. This trustworthiness level is used to reduce the strength of magnetometer-based corrections of the orientation estimate where the magnetic field distortion invalidates the assumptions necessary for those corrections.

The new algorithm addresses the three research questions …

Zinc-Oxide Nanostructure-Based Wearable Biosensor Platform For Sweat Analysis, Fahmida Alam

FIU Electronic Theses and Dissertations

The aim of this research is to develop highly sensitive, flexible, wearable enzymatic and immuno-sensor arrays for continuous and selective sensing of ethanol, lactate, and glucose in human sweat. Human sweat has clinical importance and has been recommended as an early pointer for many health conditions and diseases. Thus, for many health applications, point-of-care non-invasive monitoring of different biomarkers in sweat is ultimately important. The major challenges of the sweat analysis biosensors include selectivity, sensitivity, flexibility, sweat collection, and storage for analysis. In this research, sonochemical synthesis of two-dimensional (2D) Zinc Oxide Nanoflakes (ZnO NFs) and wearable sweat analysis biosensors …

Advance Solutions For Voltage Control And Optimization In Smart Grids, Temitayo Olayemi Olowu

FIU Electronic Theses and Dissertations

Voltage optimization and control on distribution networks is of uttermost importance to distribution system operators. The performance of the entire distribution network depends on the voltage profile of the system. The aim of this dissertation is to develop threefold advanced solutions that can effectively address and mitigate the voltage control and optimization issues of the smart grid. The first objective of this thesis is to develop accurate methods to quantify and analyze the expected variability individual and aggregated PV systems which significantly impact the voltage profile of grid-interfaced PV systems. We develop an improved statistical formulation, propose the use power …

A Study Of Magnetism And Possible Mixed-State Superconductivity In Phosphorus-Doped Graphene, Julian E. Gil Pinzon

FIU Electronic Theses and Dissertations

Evidence of superconducting vortices, and consequently mixed-state superconductivity, has been observed in phosphorus-doped graphene at temperatures as high as 260 K. The evidence includes transport measurements in the form of resistance versus temperature curves, and magnetic measurements in the form of susceptibility and magnetic Nernst effect measurements. The drops in resistance, periodic steps in resistance, the appearance of Nernst peaks and hysteresis all point to phosphorus-doped graphene having a broad resistive region due to flux flow as well as a Berezinskii-Kosterlitz-Thouless (BKT) transition at lower temperatures.

The observation of irreversible behavior in phosphorus-doped graphene under the influence of a thermal …

Cross-Mixing Hybrid Beamforming Receiver For Wideband Apertures, Rimon Hokayem

FIU Electronic Theses and Dissertations

Research is showing an interest in redefining phased arrays and devising more flexible low-profile receivers. As such, there is a need to compensate for the bulkiness of existing systems which is mainly imposed by the phase shifters placed after each element. That is, we must circumvent hardware limitations by searching for alternatives for phase shifting the signals to introduce more flexibility in signal reception for more downsized radio systems. Therefore, self-mixing arrays are developed and now deployed for the beamforming process. The concept stems from applying mixing instead of shifting to eliminate the delays in reception. Central to its realization …

Deployable Tightly Coupled Dipole Arrays For Small Satellites, Maxence Carvalho

FIU Electronic Theses and Dissertations

This dissertation presents the theory, design, fabrication, and verification of several critical components for a novel class of origami-based and deployable Tightly Coupled Dipole Arrays (TCDAs) suitable for small satellite applications. This work introduces a new approach to enhance the bandwidth of TCDAs by incorporating a semi-resistive Frequency Selective Surface (FSS) network within the substrate. The integration of this FSS network within a dual-polarized TCDA led to an increased impedance bandwidth of 28:1 from 0.20 GHz to 5.6 GHz. Concurrently, losses above 2.5 GHz are reduced to achieve a radiation efficiency of 83% on average. A major component of the …

Investigation Of Carbon-Based Label-Free Electrochemical Aptasensors For Point-Of-Care Cancer Biomarker Detection, Shahrzad Forouzanfar

FIU Electronic Theses and Dissertations

Cancer is the second cause of death, with millions of fatalities every year. The early detection of cancer can tremendously increase the survival chances of the patients. An effective approach for early detection of cancer is developing reliable and relatively cheap biosensors that can quantify the cancer biomarkers from blood samples. These classes of the biosensor are commonly referred to as point-of-care (POC) cancer biomarker biosensors. The label-free electrochemical biosensors based on carbon dravite materials can be feasible for POC cancer biomarker biosensors. The present dissertation aims to design, develop, and optimize carbon-based biosensors for label-free detection of lactic acid …

Development Of A Real-Time Single-Lead Single-Beat Frequency-Independent Myocardial Infarction Detector, Harold Martin

FIU Electronic Theses and Dissertations

The central aim of this research is the development and deployment of a novel multilayer machine learning design with unique application for the diagnosis of myocardial infarctions (MIs) from individual heartbeats of single-lead electrocardiograms (EKGs) irrespective of their sampling frequencies over a given range. To the best of our knowledge, this design is the first to attempt inter-patient myocardial infarction detection from individual heartbeats of single-lead (lead II) electrocardiograms that achieves high accuracy and near real-time diagnosis. The processing time of 300 milliseconds to a diagnosis is just at the time range in between extremely fast heartbeats of around 300 …

Textile-Integrated Wearable Radio Frequency (Rf) Wireless Power Transfer And Harvesting For Battery-Free Medical Sensing, Dieff Vital

FIU Electronic Theses and Dissertations

Body-worn sensing is becoming increasingly important for patient monitoring, particularly the elderly. The vital signs can be directly transferred to their physicians, personal caregivers or used for self-diagnosis. To achieve this, wireless, wearable, and self-powered sensors are required. Wireless RF powering/charging, implemented into clothing, upholstery, and smart dressing presents itself as a convenient and practical solution for powering wearable sensors. In this dissertation, the implementation of such wireless charging platforms that are integrated into clothing, and the integration of medical sensor electronics is shown. Fabric-based wireless charging allows for lightweight, scalable, flexible, battery- less, and comfortable wearing. It is also …

Correlating The Effect Of Dynamic Variability In The Sensor Environment On Sensor Design, Pulak Bhushan

FIU Electronic Theses and Dissertations

This dissertation studies the effect of biofluid dynamics on the electrochemical response of a wearable sensor for monitoring of chronic wounds. The research investigates various dynamic in vivo parameters and correlates them with experimentally measured behavior with wound monitoring as a use case. Wearable electrochemical biosensors suffer from several unaddressed challenges, like stability and sensitivity, that need to be resolved for obtaining accurate data. One of the major challenges in the use of these sensors is continuous variation in biofluid composition. Wound healing is a dynamic process with wound composition changing continuously. This dissertation investigates the effects of several in …

Design And Realization Of Fully-Digital Microwave And Mm-Wave Multi-Beam Arrays With Fpga/Rf-Soc Signal Processing, Sravan Kumar Pulipati

FIU Electronic Theses and Dissertations

There has been a constant increase in data-traffic and device-connections in mobile wireless communications, which led the fifth generation (5G) implementations to exploit mm-wave bands at 24/28 GHz. The next-generation wireless access point (6G and beyond) will need to adopt large-scale transceiver arrays with a combination of multi-input-multi-output (MIMO) theory and fully digital multi-beam beamforming. The resulting high gain array factors will overcome the high path losses at mm-wave bands, and the simultaneous multi-beams will exploit the multi-directional channels due to multi-path effects and improve the signal-to-noise ratio. Such access points will be based on electronic systems which heavily depend …

Reliable And Secure Drone-Assisted Millimeterwave Communications, Mai A. Abdel-Malek

FIU Electronic Theses and Dissertations

The next generation of mobile networks and wireless communication, including the fifth-generation (5G) and beyond, will provide a high data rate as one of its fundamental requirements. Providing high data rates can be accomplished through communication over high-frequency bands such as the Millimeter-Wave(mmWave) one. However, mmWave communication experiences short-range communication, which impacts the overall network connectivity. Improving network connectivity can be accomplished through deploying Unmanned Ariel Vehicles(UAVs), commonly known as drones, which serve as aerial small-cell base stations. Moreover, drone deployment is of special interest in recovering network connectivity in the aftermath of disasters. Despite the potential advantages, drone-assisted networks …

Secure Distributed Systems Over Satoshi Blockchains, Ruben Recabarren Velarde

FIU Electronic Theses and Dissertations

Distributed Ledger Technologies (DLTs) have become an important driving force towards the creation of novel distributed applications aimed at solving problems that range from digital currency tools to self governing digital democracy systems.

Our thesis is that Satoshi cryptocurrencies, i.e., Bitcoin and its variants, can be used to endow several popular distributed services with strong privacy, anonymity and censorship resistance properties that evade current solutions.

To this end, we first study the design of Satoshi cryptocurrency mining protocols, and discover and document privacy and integrity vulnerabilities of Stratum, the de-facto pooled mining protocol.

We have developed tools that exploit these …

Condition Monitoring And Fault Tolerant Control Techniques In Electric Vehicle Drives, Hassan H. Eldeeb

FIU Electronic Theses and Dissertations

With the growth in the electric vehicles (EV) use, transportation electrification methodologies ensure improved reliability and security of the EVs and its powertrain as significant factors to consider. Any failure in the EV’s motor drive system or any of its components will directly impact the powertrain's reliability and passenger safety. Due to their robustness and mature design, EV powertrains utilize vector-controlled power inverter-fed induction motor (IM) as their drive system. Therefore, fast, reliable, non-destructive, and non-invasive fault diagnosis (FD) and condition monitoring (CM) techniques are required to detect faults in EV drive systems at their development stage.

Two novel real-time …

Digital Twin-Based Cooperative Control Techniques For Secure And Intelligent Operation Of Distributed Microgrids, Ahmed Aly Saad Ahmed

FIU Electronic Theses and Dissertations

Networked microgrids play a key role in constructing future active distribution networks for providing the power system with resiliency and reliability against catastrophic physical and cyber incidents. Motivated by the increasing penetration of renewable resources and energy storage systems in the distribution grids, utility companies are encouraged to unleash the capabilities of the distributed microgrid to work as virtual power plants that can support the power systems. The microgrids nature is transforming the grid and their control systems from centralized architecture into distributed architectures. The distributed networked microgrids introduced many benefits to the future smart grids, it created many challenges …