Electrical and Computer Engineering Commons^™

Failure Study Of Silicon Gated Field Emitter Arrays: Experiment And Simulation, Rushmita Bhattacharjee

Boise State University Theses and Dissertations

Silicon-based Gated Field Emitter Arrays (Si-GFEAs) are among the most well-developed field emitters. They are being actively explored for vacuum transistors and microwave vacuum electron devices due to their high-frequency performance, radiation resistance, and thermal stability up to 400 °C. However, their long-term reliability is limited by sudden failure events, resulting in cathodic vacuum arcs. This dissertation presents a combined experimental and simulation-based investigation into arc initiation mechanisms in Si-GFEAs. Different device arrays were tested under normal operation in vacuum at 10^-7 Torr with gate voltages of 50-70 V and emission currents from tens of nA to tens of µA. …

Analysis Of Learning Mechanisms In Spiking Neural Networks With R(T) Elements And Memristive Synapses, Farhana Afrin

Boise State University Theses and Dissertations

As Moore's law ends, the conventional von Neumann computer architecture with binary-coded data representation has reached its bottleneck because of having separate computing and memory modules. In this architecture, continuous power is required due to sequential processing, making it challenging to improve efficiency further. The human brain can be regarded as the most energy-efficient computer architecture. In the brain, data is represented as small voltage pulses as spikes. That is why the neural units are called spiking neural networks (SNN). In SNNs, energy is required only when there is a spike, making it more energy efficient than the von-Neumann computer …

Traffic Prediction In 5g Networks Using Machine Learning, Hossein Mehri

Boise State University Theses and Dissertations

The advent of 5G technology promises a paradigm shift in the realm of telecommunications, offering unprecedented speeds and connectivity. However, the efficient management of traffic in 5G networks remains a critical challenge. It is due to the dynamic and heterogeneous nature of network traffic, including bursty patterns, varying user behaviors, and diverse applications, all of which demand highly accurate and adaptable prediction models to optimize network resource allocation and management. This dissertation investigates the intricate domain of traffic prediction within 5G networks, addressing the specific challenges posed by both massive machine type communication (mMTC) networks and 5G cellular networks.

The …

On-Chip Active Pulse-Clamp Stimulation (Apcs) For Rapid Recovery, Charge-Balanced Neural Stimulation, F. N. U. Tala

Boise State University Theses and Dissertations

Neurostimulations are widely utilized to modulate brains and nervous systems functions for therapeutic purposes. Traditional neurostimulation involves applying a direct current delivered to the excitable tissues to elicit neural response. There is a growing demand for a robust, rapid stimulation system that ensures chronic safety through charge balancing in vivo. This dissertation is a compilation of previously published works, detailing various board-level stimulators, an innovative on-chip stimulation technique, and a distributed modelling method.

Chapter one introduces MEDUSA, a cost-effective, multi-functional neurostimulation system capable of achieving multi-channel, arbitrary stimulation for neuroscience research.

Chapter two delves into a scripted distributed model framework …

Titanium Dioxide Nanomaterial Ink Production Through Laser Ablation Synthesis In Solution For Printed Electronics Applications, Devyn Duryea, Nicholas Mckibben, Jacob Manzi, Taylor Brennan, Harish Subbaraman, David Estrada, Nirmala Kandadai

Electrical and Computer Engineering Faculty Publications and Presentations

Flexible and printed electronics have become increasingly popular as they make possible the production of flexible, low-cost, multifunction devices that are unachievable through traditional manufacturing methods. The printed films are significantly impacted and thus limited by the existing ink production process. Herein, an alternate technique of generating high-quality titanium dioxide (TiO₂) nanoparticle ink compatible with aerosol jet printing using laser ablation synthesis in solution (LASiS) is showcased. Dynamic light scattering data and transmission electron microscopy confirm the particle size distribution. UV–vis measurements are performed, and the Beer–Lambert relationship is used to determine the concentration of the generated ink. …

Exploring The Effects Of Dopants On The Opto-Electrical Response Of Ge2Se3-Based Optically Gated Transistor (Ogt), Md Faisal Kabir

Boise State University Theses and Dissertations

In this work, the electrical and optical responses of chalcogenide glass (ChG) Ge₂Se₃-based optically gated transistors (OGTs) were investigated. The device can act as a selector for resistive memory devices and potentially enable the production of functional high-density resistive (and memristive) arrays.

The OGT was developed using a Ge₂Se₃-based material heterostructure and demonstrated to successfully gate a memristor with light. The light intensity provided a built-in compliance current, allowing multi-state programming. By varying the light intensity incident on Ge₂Se₃ material, a family of current-voltage (I-V) curves were measured that …

Investigating Customer Churn In Banking: A Machine Learning Approach And Visualization App For Data Science And Management, Pahul Preet Singh, Fahim Islam Anik, Rahul Senapati, Arnav Sinha, Nazmus Sakib, Eklas Hossain

Electrical and Computer Engineering Faculty Publications and Presentations

Customer attrition in the banking industry occurs when consumers quit using the goods and services offered by the bank for some time and, after that, end their connection with the bank. Therefore, customer retention is essential in today’s extremely competitive banking market. Additionally, having a solid customer base helps attract new consumers by fostering confidence and a referral from a current clientele. These factors make reducing client attrition a crucial step that banks must pursue. In our research, we aim to examine bank data and forecast which users will most likely discontinue using the bank’s services and become paying customers. …

Electron Trajectories And Critical Current In A Two-Dimensional Planar Magnetically Insulated Crossed-Field Gap, Xiaojun Zhu, Jack K. Wright, N. R. Sree Harsha, Jim Browning, Allen L. Garner

Electrical and Computer Engineering Faculty Publications and Presentations

The critical current in a one-dimensional (1D) crossed-field gap is defined by the transition from a cycloidal flow to a near-Brillouin (nB) state characterized by electron flow orthogonal to both the electric and magnetic fields and uniform virtual cathode formation. Motivated by recent studies on space-charge-limited current in non-magnetic diodes, we assess the meaning of critical current in a magentically insulated two-dimensional (2D) planar crossed-field geometry. Particle-in-cell (PIC) simulations demonstrate that binary behavior between a laminar and turbulent state does not occur in 2D because the virtual cathode is nonuniform. Rather than a distinct nB state above the critical current …

Effect Of Water Vapor Desorption On The Performance Of Gallium Nitride Field Emitter Array, Ranajoy Bhattacharya, Pao-Chuan Shih, Tomás Palacios, Jim Browning

Electrical and Computer Engineering Faculty Publications and Presentations

We are exploring the potential of gallium nitride (GaN) field emitter arrays in vacuum channel transistors. This study investigated the impact of ultraviolet (UV) light on the emission properties of large arrays of GaN field emitters. Arrays of 150 × 150 emitters were analyzed before and after UV exposure. With a constant collector voltage of 200 V DC, gate voltage sweeps from 0 to 60 V were applied. The initial I–V measurements showed a rapid increase in emission current, indicating a conditioning effect, settling at a stable value of 1.25 μA after three to five sweeps. Remarkably, exposure to …

Simulation Modelling Of Silicon Gated Field Emitter Based Electronic Circuits, Robert Hay, Ranajoy Bhattacharya, Winston Chern, Girish Rughoobur, Akintunde I. Akinwande, Jim Browning

Electrical and Computer Engineering Faculty Publications and Presentations

Vacuum transistors (VTs) are promising candidates in electronics due to their fast response and ability to function in harsh environments. In this study, several oscillator and logic gate circuit simulations using VTs are demonstrated. Silicon-gated field emitter arrays (Si-GFEAs) with 1000 × 1000 arrays were used experimentally to create a VT model. First, transfer and output characteristics sweeps were measured, and based on those data, an LTspice vacuum transistor (VT) model was developed. Then, the model was used to develop Wein and Ring oscillator circuits. The circuits were analytically simulated using LTspice, where the collector bias voltage was 200 V …

Investigating Combined Extreme Weather Effects On Solar Module Through Hardware And Simulink Performance Evaluation, Amir Botros

Boise State University Theses and Dissertations

Worldwide adoption of photovoltaic (PV) cells, which use the photovoltaic effect to convert solar energy into electricity, has led to their emergence as a significant source of electricity production. As the number of PV installations continues to grow, understanding the impact of environmental factors on solar module performance becomes paramount.

Factors such as intermittency, cloud cover, shading, and nighttime unavailability significantly affect the efficiency and longevity of solar modules. However, there is a shortage of research connecting extreme weather conditions to overall module performance, hindering informed implementation decisions.

This study addresses the need for continuous monitoring of solar systems under …

Optical And Electrical Interfaces For Biological Structures, Mehdi Bandali

Boise State University Theses and Dissertations

This dissertation presents novel solutions for recording optical and electrical data from biological structures. CHAPTER ONE discusses the 16×16 Time correlated SPAD image array I developed in a 180 nm HV CMOS process for single-molecule localization super-resolution microscopy (SRM). This image array has a maximum frame rate of 80 MHz and a fill factor of 17.4 %. To demonstrate SRM with this imaging array, we localized gold nanoparticle displacement at 40 nm. CHAPTER TWO discusses stimulation artifacts' time and frequency domain characteristics and potential strategies for canceling this interference on neural recording. CHAPTER THREE discusses an artifact-resilient neural recording front-end …

Effect Of Ultraviolet Light On Field Emission Performance And Lifetime Of Lateral Field Emitter Devices, Ranajoy Bhattacharya, Marco Turchetti, Matthew Yeung, P. Donald Keathley, Karl K. Berggren, Jim Browning

Electrical and Computer Engineering Faculty Publications and Presentations

Lateral field emission devices have been characterized before and after ultraviolet (UV) light exposure. Two types of planar device structures, diode and bowtie, were studied. These nanoscale devices have 9–15 nm tip-to-tip (bowtie) or tip-to-collector (diode) dimensions with the tips fabricated from Au/Ti. Typical currents of 2–5 nA per tip at 6 V were measured. It was observed that after UV exposure, the collected current was reduced by > 28% for the case of a bowtie device; whereas the current was reduced by > 39% for the case of a diode device. This reduction can be attributed to water vapor desorption on …

Generation Of Dna Oligomers With Similar Chemical Kinetics Via In-Silico Optimization, Michael Tobiason, Bernard Yurke, William L. Hughes

Electrical and Computer Engineering Faculty Publications and Presentations

Networks of interacting DNA oligomers are useful for applications such as biomarker detection, targeted drug delivery, information storage, and photonic information processing. However, differences in the chemical kinetics of hybridization reactions, referred to as kinetic dispersion, can be problematic for some applications. Here, it is found that limiting unnecessary stretches of Watson-Crick base pairing, referred to as unnecessary duplexes, can yield exceptionally low kinetic dispersions. Hybridization kinetics can be affected by unnecessary intra-oligomer duplexes containing only 2 base-pairs, and such duplexes explain up to 94% of previously reported kinetic dispersion. As a general design rule, it is recommended that unnecessary …

Enhanced Hardware Trojan Detection In Chips By Reducing Linearity Between Features, Alfred M. S. Moussa

Boise State University Theses and Dissertations

Globally, there has been an increase in demand for System on Chip (SoC) applications, active medical implants, and Internet of Things (IoT) devices. However, due to challenges in the global supply chain, the design, fabrication, and testing of Integrated Circuits are often outsourced to untrusted third-party entities around the world rather than a single trusted entity. This situation presents an opportunity for adversaries to compromise the device’s integrity, performance, and functionality by inserting malicious modifications known as Hardware Trojans (HTs) into the original design. HTs can also create a backdoor in the system for malicious alterations.

The problem of hardware …

Investigation Of Degradation Of Solar Photovoltaics: A Review Of Aging Factors, Impacts, And Future Directions Toward Sustainable Energy Management, Eklas Hossain

Electrical and Computer Engineering Faculty Publications and Presentations

The degradation of solar photovoltaic (PV) modules is caused by a number of factors that have an impact on their effectiveness, performance, and lifetime. One of the reasons contributing to the decline in solar PV performance is the aging issue. This study comprehensively examines the effects and difficulties associated with aging and degradation in solar PV applications. In light of this, this article examines and analyzes many aging factors, including temperature, humidity, dust, discoloration, cracks, and delamination. Additionally, the effects of aging factors on solar PV performance, including the lifetime, efficiency, material degradation, overheating, and mismatching, are critically investigated. Furthermore, …

Three-Port Bi-Directional Dc–Dc Converter With Solar Pv System Fed Bldc Motor Drive Using Fpga, Arun Kumar Udayakumar, Raghavendra Rajan Vijaya Raghavan, Mohamad Abou Houran, Rajvikram Madurai Elavarasan, Anushkannan Nedumaran Kalavathy, Eklas Hossain

Electrical and Computer Engineering Faculty Publications and Presentations

The increased need for renewable energy systems to generate power, store energy, and connect energy storage devices with applications has become a major challenge. Energy storage using batteries is most appropriate for energy sources like solar, wind, etc. A non-isolated three-port DC–DC-converter energy conversion unit is implemented feeding the brushless DCmotor drive. In this paper, a non-isolated three-port converter is designed and simulated for battery energy storage, interfaced with an output drive. Based on the requirements, the power extracted from the solar panel during the daytime is used to charge the batteries through the three-port converter. The proposed three-port converter …

Investigating R(T) Functions For Spike-Timing-Dependent Plasticity In Memristive Neural Networks, Farhana Afrin, Kurtis D. Cantley

Electrical and Computer Engineering Faculty Publications and Presentations

Brain-inspired neuromorphic computation can be extremely efficient at very large scales due to inherent parallelism, scalability, and fault and failure tolerance. One widely used, biologically plausible synaptic learning mechanism is spike-timing-dependent plasticity (STDP). The proposed generic model of time-varying resistance, or R(t) elements in this work, can produce classical and beyond classical STDP in electronic spiking neural networks with memristive synapses. Hebbian and Anti-Hebbian STDP is verified with the proposed generic R(t) model by tuning the R(t) function. By appropriately placing R(t) functions with selective resistance values, symmetric or non-classical STDP learning behavior is achieved.

Character Spotting And Autonomous Tagging: Offline Handwriting Recognition For Bangla, Korean And Other Alphabetic Scripts, Nishatul Majid, Elisa H. Barney Smith

Electrical and Computer Engineering Faculty Publications and Presentations

This paper demonstrates a framework for offline handwriting recognition using character spotting and autonomous tagging which works for any alphabetic script. Character spotting builds on the idea of object detection to find character elements in unsegmented word images. An autonomous tagging approach is introduced which automates the production of a character image training set by estimating character locations in a word based on typical character size. Although scripts can vary vividly from each other, our proposed approach provides a simple and powerful workflow for unconstrained offline recognition that should work for any alphabetic script with few adjustments. Here we demonstrate …

A Retrospective On 2022 Cyber Incidents In The Wind Energy Sector And Building Future Cyber Resilience, Megan Egan

Cyber Operations and Resilience Program Graduate Projects

Between February and June 2022, multiple wind energy sector companies were hit by cyber-attacks impacting their ability to monitor and control wind turbines. With projected growth in the United States of 110.66 GW from 2020 to 2030, wind energy will increasingly be a critical source of electricity for the United States and an increasingly valuable target for cyberattacks. This paper shows the importance of redundant remote communications, secure third-party providers, and improving response and recovery processes that would ensure this growth period fulfills its potential as a unique opportunity to build in cyber resilience from the outset of new installations …

Soc Reconfigurable Architecture For Software-Trained Neural Networks On Fpga, Michael Wasef

Boise State University Theses and Dissertations

Neural networks are extensively used in software and hardware applications. In hardware applications, it is necessary to implement a small, accelerated, and configurable hardware architecture to be easily embedded in hardware devices to implement and execute the required neural network with superior performance. Such configurable hardware architecture allows the user to implement neural networks with different structures and easily modify or change them as needed.

In this dissertation, three architectures, each containing three layers, have been designed using a system-on-chip approach and implemented on a Field Programmable Gate Array (FPGA), to realize and accelerate the performance of three types of …

Interleaved Honeypot-Framing Model With Secure Mac Policies For Wireless Sensor Networks, Rajasoundaran Soundararajan, Maheswar Rajagopal, Akila Muthuramalingam, Eklas Hossain, Jaime Lloret

Electrical and Computer Engineering Faculty Publications and Presentations

The Wireless Medium Access Control (WMAC) protocol functions by handling various data frames in order to forward them to neighbor sensor nodes. Under this circumstance, WMAC policies need secure data communication rules and intrusion detection procedures to safeguard the data from attackers. The existing secure Medium Access Control (MAC) policies provide expected and predictable practices against channel attackers. These security policies can be easily breached by any intelligent attacks or malicious actions. The proposed Wireless Interleaved Honeypot-Framing Model (WIHFM) newly implements distributed honeypot-based security mechanisms in each sensor node to act reactively against various attackers. The proposed WIHFM creates an …

Tropospheric Attenuation Prediction For Future Millimeter Wave Terrestrial Systems: Estimating Statistics And Extremes, Jinwen Liu, David W. Matolak, Ismail Güvenç, Hani Mehrpouyan

Electrical and Computer Engineering Faculty Publications and Presentations

Tropospheric attenuations can be significant in the millimeter wave (mmWave) frequency bands; hence, accurate prediction modeling of tropospheric attenuation is important for reliable mmWave communication. Several models have been established by the International Telecommunication Union (ITU), yet estimation accuracy is limited due to the large spatial scales used for model input parameters. In this paper, we address this and apply local precipitation data to analyze tropospheric attenuation statistics and compare to results when using ITU regional input rain data. Specifically, tropospheric attenuation is predicted via simulations using the ITU method at 30, 60, and 90 GHz in four distinct geographic …

Laser-Induced Galfenol Embedded Multi-Layer Graphene-Oxide In Solution, Devyn Duryea, Nirmala Kandadai

Electrical and Computer Engineering Faculty Publications and Presentations

The proposed work demonstrates the direct synthesis of nanomaterial-embedded laser-induced few-layer graphene-oxide by directly ablating galfenol in a water-based solution for the first time. Laser-induced multilayer graphene-oxide (GO) embedded with galfenol (gallium–iron alloy) nanoparticles (NPs) is created through a method of direct laser inscription of bulk galfenol in deionized (DI) water with femtosecond laser ablation. The NP-embedded GO is achieved by irradiating a near-infrared (near-IR) femtosecond laser at 1040 nm on a bulk galfenol material submerged in a solution comprising DI water and a small concentration (5%/wt.) of polyvinylpyrrolidone followed by a second ablation in pure DI water. Results show …

Ultra-Compact Hybrid Silicon: Chalcogenide Waveguide Temperature Sensor, Bahareh Badamchi, Wei-Che Hsu, Al-Amin Ahmed Simon, Zong Yin Chi, Jacob Manzi, Maria Mitkova, Alan X. Wang, Harish Subbaraman

Electrical and Computer Engineering Faculty Publications and Presentations

We demonstrate a real-time, reusable, and reversible integrated optical sensor for temperature monitoring within harsh environments. The sensor architecture combines the phase change property of chalcogenide glasses (ChG) with the high-density integration advantages of high index silicon waveguides. To demonstrate sensor feasibility, ChG composition Ge₄₀S₆₀, which is characterized by a sharp phase transition from amorphous to crystalline phase around 415 °C, is deposited over a 50 µm section of a single mode optical waveguide. The phase transition changes the behavior of Ge₄₀S₆₀ from a low loss to high loss material, thus significantly …

Data-Driven Passivity-Based Control Of Underactuated Robotic Systems, Wankun Sirichotiyakul

Boise State University Theses and Dissertations

Classical control strategies for robotic systems are based on the idea that feedback control can be used to override the natural dynamics of the machines. Passivity-based control (Pbc) is a branch of nonlinear control theory that follows a similar approach, where the natural dynamics is modified based on the overall energy of the system. This method involves transforming a nonlinear control system, through a suitable control input, into another fictitious system that has desirable stability characteristics. The majority of Pbc techniques require the discovery of a reasonable storage function, which acts as a Lyapunov function candidate that can be …

Seamless Transition Of A Microgrid Between Grid-Connected And Islanded Mode, Julie B. Matarweh

Boise State University Theses and Dissertations

This thesis focuses on improving the behavior of inverters during transition periods from islanded mode to grid-connected mode (GC) and vice-versa. A systematic approach is presented to add smart features to inverters to enhance their capability to cope with sudden changes in the power system.

The importance of microgrids lies in their ability to provide a stable and reliable source of power for critical loads in the presence of faults. For this purpose, a design is proposed consisting of a distributed energy resource (DER), battery energy storage system (BESS) and a load connected through a bypass switch with the main …

Process-Property Linkages Construction For Inkjet Printing With Machine Learning, Fataneh Jenabi

Boise State University Theses and Dissertations

Printed electronics are emerging technologies that can potentially revolutionize the manufacturing of electronic devices. One promising technology for printed electronics is inkjet printing. Inkjet printing offers both low-cost processing and high resolution. Being a subset of additive manufacturing, inkjet printing minimizes waste and is compatible with a wide range of inks. However, inkjet printing of electronic devices is still in its infancy. One major challenge for inkjet printing is the complexity of the process optimization and uncertain high throughput production. To achieve a high-quality print, there is a complex parameter space of materials and processing parameters that needs to be …

Strategies For Controlling The Spatial Orientation Of Single Molecules Tethered On Dna Origami Templates Physisorbed On Glass Substrates: Intercalation And Stretching, Keitel Cervantes-Salguero, Austin Biaggne, John M. Youngsman, Brett M. Ward, Young C. Kim, Lan Li, John A. Hall, William B. Knowlton, Elton Graugnard, Wan Kuang

Electrical and Computer Engineering Faculty Publications and Presentations

Nanoarchitectural control of matter is crucial for next-generation technologies. DNA origami templates are harnessed to accurately position single molecules; however, direct single molecule evidence is lacking regarding how well DNA origami can control the orientation of such molecules in three-dimensional space, as well as the factors affecting control. Here, we present two strategies for controlling the polar (θ) and in-plane azimuthal (ϕ) angular orientations of cyanine Cy5 single molecules tethered on rationally-designed DNA origami templates that are physically adsorbed (physisorbed) on glass substrates. By using dipolar imaging to evaluate Cy5′s orientation and super-resolution microscopy, the absolute …

Experimental Validation Of A Reflective Long Period Grating Design Methodology, Sohel Rana, Nirmala Kandadai, Harish Subbaraman

Electrical and Computer Engineering Faculty Publications and Presentations

In this work, we present an experimental demonstration of our previously published modeling work on reflective long period grating (LPG). To provide the practical realization of the modeling work, we coat a long segment of fiber both in the tail length and the end facet beyond the gratings with silver to invert the transmission mode LPG to reflection mode LPG. We then measure the LPG characteristics in both the transmission and reflection mode and validate our findings from modeling work. We further build temperature and refractive index (RI) sensors and demonstrate temperature sensing from 21 °C to 191 °C with …