Defense Notices
All students and faculty are welcome to attend the final defense of EECS graduate students completing their M.S. or Ph.D. degrees. Defense notices for M.S./Ph.D. presentations for this year and several previous years are listed below in reverse chronological order.
Students who are nearing the completion of their M.S./Ph.D. research should schedule their final defenses through the EECS graduate office at least THREE WEEKS PRIOR to their presentation date so that there is time to complete the degree requirements check, and post the presentation announcement online.
Upcoming Defense Notices
Muhammad Momin Rahman
Development of a Signal Flow Graph-Based De-Embedding Framework for Broadband Passive Linear Multiport RF & Microwave Networks with Applications to Power SplittersWhen & Where:
Nichols Hall, Room 317 (Richard K. Moore Conference Room)
Committee Members:
Carl Leuschen, ChairKenneth Demarest
Fernando Rodriguez-Morales
Abstract
Discrete passive components, including resistors, capacitors, inductors, and transformers, are fundamental to broadband 75-Ω radio-frequency (RF) systems, particularly in cable television (CATV) and hybrid fiber-coaxial (HFC) networks. These components are incorporated into power splitters, couplers, power inserters, and amplifiers to achieve desired frequency responses, impedance matching, and signal transmission characteristics. However, their electrical behavior becomes increasingly complex at higher frequencies due to parasitic resistance, inductance, capacitance, electromagnetic coupling, and distributed transmission-line effects. Consequently, accurate broadband characterization is essential for predicting component behavior and developing representative RF circuit models for simulation purposes.
A significant challenge arises when characterizing passive components with limited or unavailable manufacturer specifications, particularly when existing component inventories must be evaluated for broadband applications. Conventional measurement instruments, including digital multimeters, LCR meters, oscilloscopes, and function generators, generally lack the frequency range required for comprehensive RF characterization from 5 MHz to 3 GHz. Vector network analyzers (VNAs) enable complex scattering-parameter measurements across this frequency range; however, the measured response includes contributions from test fixtures, interconnections, and parasitic discontinuities that must be distinguished from the intrinsic response of the device under test (DUT).
This project investigates the development of a signal flow graph (SFG)-based de-embedding framework for broadband passive linear multiport RF networks. The methodology incorporates series-through and shunt-through DUT (CPWG) fixture configurations, conventional Open-Short and Short-Open de-embedding techniques, followed by lumped-element and distributed transmission-line representations of fixture parasitics. Scattering-parameter and ABCD-parameter analysis are employed to characterize fixture responses, while signal flow graph derivations provide a mathematical basis for analyzing interconnected multiport networks. Particular attention is given to fixture asymmetry, impedance discontinuities, and multiple signal propagation paths that complicate the extension of conventional two-port characterization methods to higher-order networks.
Experimental validation is conducted through the characterization of passive components with published impedance and quality-factor characteristics, enabling comparisons between extracted measurements, equivalent-circuit models, and manufacturer reference data. The methodology is subsequently applied to broadband power splitter networks used in CATV/HFC systems to investigate the accuracy and applicability of the proposed multiport de-embedding framework. The project aims to establish a systematic approach to broadband passive component characterization that integrates fixture modeling, network theory, and experimental measurement while reducing dependence on proprietary characterization data.
Fairuz Shadmani Shishir
Efficient and Privacy-Preserving Biomedical AI: From Precision Therapeutics Design to Private Clinical PredictionWhen & Where:
Eaton Hall, Room 2001B
Committee Members:
Sumaiya Shomaji, ChairTamzidul Hoque
Cuncong Zhong
Bishnu Sarker
Michael Hageman
Abstract
Accurate protein characterization, precision therapeutics design, and privacy-preserving clinical modeling are important challenges in biomedical artificial intelligence (AI). Addressing these challenges requires computational frameworks that are not only accurate and scalable but also capable of supporting reliable decision-making. This dissertation develops efficient, scalable, and reliable computational frameworks across three areas: Computational characterization of proteins, precision therapeutics design, and privacy-aware clinical representation learning. The first part of this dissertation focuses on efficient protein characterization at both the sequence and residue levels. GPCR-SLM, a knowledge-distilled small protein language model, classifies G-protein-coupled receptors (GPCRs), a family targeted by approximately 35% of FDA-approved drugs. Across 86 families, GPCR-SLM achieves 99% accuracy, outperforming BLAST (86.4%) and HMMER (91%), with a 33.5-fold speedup over large protein language models. Extending characterization to the residue level, a protein-metal-ion binding site prediction framework evaluates five protein language models and incorporates positional encoding to capture long-range dependencies. Under 10-fold cross-validation, it achieves a Matthews correlation coefficient of 0.89, with precision, recall, and F1 scores exceeding 95% across six metal ions.
Building on these protein characterization methods, the second part advances precision therapeutics design through uncertainty quantification and generative learning for therapeutic antibodies. NbBayesLM combines protein language model embeddings and physicochemical descriptors in a Bayesian neural network to predict nanobody thermostability. Evaluated on 10,630 VHH sequences, it achieves a mean absolute error of 1.89C and an R2 of 0.67 while estimating epistemic and aleatoric uncertainty to support candidate prioritization. CIgFlow employs classifier-free guidance to generate de novo, antigen-conditioned antibody sequences without fixed scaffolds or paired structural data. Generated sequences achieve a median OASis humanness score of 0.90 and mean predicted local distance difference test (pLDDT) score of 85.0, demonstrating promising novelty and diversity. The third part addresses privacy-aware clinical modeling using electrocardiograms (ECGs), which encode diagnostic information and sensitive demographic attributes. A variational autoencoder with dual discriminators suppresses demographic information while preserving clinically relevant representations.
Collectively, this dissertation advances efficient protein representation learning, computational antibody design, and privacy-preserving clinical AI, contributing methodological foundations for trustworthy biomedical applications.
Arturo Solorio
Performance Analysis of Mismatched Filtering for Stochastic WaveformsWhen & Where:
Nichols Hall, Room 246 (Executive Conference Room)
Committee Members:
Patrick McCormick, ChairShannon Blunt
Charles Mohr
Abstract
Mismatched filtering (MMF) is a widely used pulse compression technique that reduces cross-correlation sidelobe levels at the cost of some loss in signal-to-noise ratio (SNR). Applying MMF to stochastically generated radar waveforms makes the filter's performance inherently random, which can be problematic if the variability is excessive. As well as the computational cost being relatively high, as per pulse, a new MMF optimization is required. In this thesis, the feasibility of a fixed MMF strategy for stochastic radar waveforms to reduce computational cost is investigated. Two MMF formulations were evaluated, the optimal MMF (Diagonal Loaded Filter) and a projection-based MMF. Both filters were designed to minimize sidelobe energy within specified regions of the Cross-Ambiguity Function (CAF) for Stochastic Waveform Generation (StoWGe) waveforms, and their performance was assessed across multiple time-bandwidth products and sidelobe-regions for two center frequencies, Fc = 30 Ghz and Fc = 3.5 Ghz. The MMF performance was characterized using SNR loss and sidelobe depth over hundreds of trails. It is observed that the variability in SNR and sidelobe depth decreases as the waveform time-bandwdith product and the sidelobe region targeted for minimization increase, although the Fc = 3.5 GHz cases exhibited a plateau in achievable sidelobe depth. Additional validation using 1000-trail histograms and loop-back testing confirmed the robustness for the fixed MMF approach for higher time-bandwidth product stochastic waveforms. Where, overall, the results demonstrate that a fixed MMF strategy is feasible for stochastic waveforms when the time-bandwdith product and sidelobe region are sufficiently large. Furthermore, the Projection-based MMF provides a suboptimal alternative to the optimal MMF as it achieves comparable MMF performance when constrained to similar SNR-loss and may be desirable when the size of the domination eigenvalues is small relative to the filter length and can be efficiency obtained.
Past Defense Notices
SOUMYAROOP NANDI
Robust Object Tracking and Adaptive Detection for Autonavigation of Unmanned Aerial VehicleWhen & Where:
246 Nichols Hall
Committee Members:
Richard Wang, ChairJim Rowland
Jim Stiles
Abstract
Object detection and tracking is an important research topic in the computer vision field with numerous practical applications. Although great progress has been made, both in object detection and tracking over the last decade, it is still a big challenge in real-time applications like automated navigation of an unmanned aerial vehicle and collision avoidance with a forward looking camera. An automated and robust object tracking approach is proposed by integrating a kernelized correlation filter framework with an adaptive object detection technique based on minimum barrier distance transform. The proposed tracker is automatically initialized with salient object detection and the detected object is localized in the image frame with a rectangular bounding box. An adaptive object redetection strategy is proposed to refine the location and boundary of the object, when the tracking correlation response drops below a certain threshold. In addition, reliable pre-processing and post-processing methods are applied on the image frames to accurately localize the object. Extensive quantitative and qualitative experimentation on challenging datasets have been performed to verify the proposed approach. Furthermore, the proposed approach is comprehensively examined with six other recent state-of-the-art¬ trackers, demonstrating that the proposed approach greatly outperforms these trackers, both in terms of tracking speed and accuracy.
TRUC ANH NGUYEN
ResTP: A Configurable and Adaptable Multipath Transport Protocol for Future Internet ResilienceWhen & Where:
246 Nichols Hall
Committee Members:
James Sterbenz, ChairVictor Frost
Bo Luo
Gary Minden
Justin Rohrer
Abstract
With the motivation to develop a resilient and survivable networking system that can cope with challenges posed by the rapid growth in networking technologies and use paradigms and the impairments of TCP and UDP, we propose a general-purpose, configurable and adaptable multipath-capable transport-layer protocol called ResTP. By supporting cross- layering, ResTP allows service tuning by the upper application layer while promptly reacting to the underlying network dynamics by using the feedback from the lower layer. Our composable ResTP not only has the flexibility to provide services to different application classes operating across various network environments, its selection of mechanisms also increases the resilience level of the system in which it is deployed since the design of ResTP is guided by a set of principles derived from the ResiliNets framework. Moreover, the implementation of ResTP employs modular programming to minimize the complexity while increasing its extensibility. Hence, the addition of any new algorithms to ResTP would require only some small changes to the existing code. Last but not least, many ResTP components, including its header, are optimized to reduce unnecessary overhead. In this proposal, we introduce ResTP’s key functionalities, present some preliminary simulation results of ResTP in comparison with TCP and UDP in ns-3, and discuss our plan towards the completion and analysis of the protocol. The results show that ResTP is a promising transport-layer protocol for Future Internet (FI) resilience.
JUSTIN DAWSON
Remote Monads and Remote ApplicativesWhen & Where:
246 Nichols Hall
Committee Members:
Andy Gill, ChairPerry Alexander
Prasad Kulkarni
Bo Luo
Kyle Camarda
Abstract
Remote Procedure Calls (RPCs) are an integral part of the internet of things. After the introduction of RPCs, there have been a number of optimizations to amortize the network overhead, including the addition of asynchronous calls and batching requests together. In Haskell, we have discovered a principled way to compose procedure calls together using the Remote Monad mechanism. A remote monad has primitive operations that evaluate outside the local runtime system and is a generalization of RPCs. Remote Monads use natural transformations to make modular and composable network stacks which can automatically bundle requests into packets in a principled way, making them easy to adapt for a number of applications. We have created a framework which has been successfully used to implement JSON-RPC, a graphical browser-based library, an efficient bytestring implementation, and database queries. The result of this investigation is that the cost of implementing bundling for remote monads can be amortized almost for free, if given a user-supplied packet transportation mechanism.
GHAITH SHABSIGH
Covert Communications in the RF Band of Primary Wireless NetworksWhen & Where:
250 Nichols Hall
Committee Members:
Victor Frost, ChairShannon Blunt
Lingjia Liu
Erik Perrins
Tyrone Duncan
Abstract
Covert systems are designed to operate at a low probability of detection in order to provide system protection at the physical layer level. The classical approach to covert communications aims at hiding the covert signal in noise by lowering the power spectral density of the signal to a level that makes it indistinguishable from that of the noise. However, the increasing demand for modern covert systems that can provide better protection against intercept receivers (IRs) and provides higher data rates has shifted the focus to the design of Ad-Hoc covert networks (ACNs) that can hide their transmission in the RF spectrum of primary networks (PNs). The early work on exploiting the RF band of other wireless systems has been promising; however, the difficulties in modeling such environments, and analyzing the impact on/from the primary network have limited the work on this crucial subject. In this work, we provide the first comprehensive analyses of a covert network that exploits the RF band of an OFDM-based primary network to achieve covertness. A spectrum access algorithm is presented which would allow the ACN to transmit in the RF spectrum of the PN with minimum interference. Next, we use stochastic geometry to model both the OFDM-based PN as well as the ACN. Using stochastic geometry would also allow us to provide a comprehensive analysis for two metrics, namely an aggregate metric and a ratio metric. These two metrics quantify the covertness and performance of the covert network from the perspective of the IR and the ACN, respectively. The two metrics are used to determine the detectability limits of an ACN by an IR. The two metrics along with the proposed spectrum access algorithm will be used to provide a comprehensive discussion the design the ACN for a target covertness level, and analyze the effect of the PN parameters on the ACN expected performance. This work also addresses the question of trade-off between the ACN covertness and its achievable throughput. The overall research work illustrates the strong potential for using man-made transmissions as a mask for covert communications.
RAHUL BAID
Applying Machine Learning through Programming LabsWhen & Where:
2001B Eaton Hall
Committee Members:
Nicole Beckage, ChairJerzy Grzymala-Busse
Fengjun Li
Abstract
The goal of this project is to bring together the complexity of core mathematics with programming abilities to code machine learning algorithms that can be incorporated into programming labs and exercises for graduate and undergraduate machine learning students.
The aim of building the labs is to provide students with a learning tool to gain a better understanding of the inner workings of machine learning algorithms. Additionally, the labs aim to expose what challenges each algorithm can bring on its own. SAS Analytics brings into perspective machine learning methods by explaining that machine learning enables “high-value predictions that can guide better decisions and smart actions in real time without human intervention.”[2] Machine learning methods can be applied to a wide spectrum of domains and therefore, rather than attempting to cover all the algorithms, I have incorporated the algorithms that are widely applicable and explore key mathematical concepts. These algorithms for machine learning labs will give the students a learning approach to solving the intricacies of the underlying mathematical principles and will also help students to make better decisions about algorithm design and develop more accurate model predictions.
Since each machine learning lab focuses on a particular algorithm, each program comes with a different challenge. To write these labs, I first had to master the material, which entailed finding the purpose of the algorithm and the statistical knowledge involved. Through these findings, I developed labs with specific designs, datasets, and evaluation metrics. A key difference between this approach and many other machine learning textbook approaches is that the students are building up these individual labs from scratch. They are asked to write, for a variety of different algorithms, the cost/loss function, the optimization procedure and even basic evaluation metrics. While it may be easier to call a function within a programming language, it is also easy to violate assumptions or requirements of these algorithms. By programming algorithms from scratch, as students must do in this lab, they are better able to draw parallels between the applied and theoretical underpinnings of these algorithms.
AKHILESH MISHRA
Multi-look SAR Processing and Array Optimization Applied to Radio Echo Sounding of Ice SheetsWhen & Where:
317 Nichols Hall
Committee Members:
Carl Leuschen, ChairStephen Yan
Prasad Gogineni
Abstract
Increase in sea level is a problem of global importance because of its impact on infrastructure and residents in coastal regions. Airborne and satellite observations have shown that the margins of Greenland and Antarctic ice sheets are melting and retreating, steadily increasing their contribution to sea level rise over the last decade. To understand the ice dynamics and develop models to generate accurate estimates of ice sheets’ future contribution to sea level rise, more information on ice thickness and basal conditions are required. Airborne ice penetrating radars are routinely deployed on long-range aircraft to perform ice thickness measurements, which are needed to derive information on bed topography and basal conditions. Acquiring useful radar reflections from the ice-bed interface is very challenging in regions where ice sheets are exhibiting the most rapid changes because returns from the ice-bed are very weak and often masked by the off nadir surface clutter. Advanced signal processing techniques, such as Synthetic Aperture Radar (SAR) and array processing, are required to filter the clutter and extract weak bed echoes buried in the noise. However, past attempts to detect these signals have not been completely successful because system and target-induced errors on SAR and array processing are not fully compensated. SAR processing in areas with significant surface slope degrades signal-to-noise ratio. Also, systematic and random errors in amplitude and phase between receive channels degrade the performance of array processors used to synthesize cross-track beam pattern.
A novel Multi-look Time Domain Back Projection (MLTDBP) parallel processor has been developed to accurately model the electromagnetic wave propagation through the ice and generate echograms with better SNCR (Signal to Noise-Clutter Ratio) in the along-track dimension. A novel dynamic channel equalization method (based on null optimization) has been developed to adaptively calibrate the receive channels, giving an improved SNCR for the cross-track processing algorithms. Results from two-dimensional processing algorithms have been shown to be effective in extracting weak bed echoes, sloped internal ice layers, deep internal ice layers; and these results are also used to generate 3D ice-bed map of fast flowing Kangiata Nunaata Sermia (KNS) glacier in southwest Greenland.
SUSOBHAN DAS
Tunable Nano-photonic DevicesWhen & Where:
246 Nichols Hall
Committee Members:
Ron Hui, ChairAlessandro Salandrino
Chris Allen
Jim Stiles
Judy Wu
Abstract
High speed photonic systems and networks require electro-optic modulators to encode electronic signal onto optical carrier. The central focus of this research is twofold. First, tunable properties and tuning mechanisms of optical materials like Graphene, Vanadium dioxide (VO2), and Indium Tin Oxide (ITO) are characterized systematically in the 1550nm telecommunication wavelength. Then, these materials are implemented to design novel nano-photonic devices with high efficiency and miniature footprint suitable for photonic integration.
Specifically, we experimentally investigated the complex index of graphene in near infrared (NIR) wavelength through the reflectivity measurement on a SiO2/Si substrate. The measured change of reflectivity as the function of applied gate voltage is highly correlated with the Kubo formula. Based on a fiber-optic pump-probe setup we demonstrated that short optical pulses can be translated from pump wavelength to probe wavelength through dielectric-to-metal phase transition of VO2. In this process, pump leading edge induced optical phase modulation on the probe is converted into an intensity modulation through an optical frequency discriminator. We also theoretically modeled the permittivity of ITO with different levels of doping concentration in NIR region.
We proposed an ultra-compact electro-optic modulator based on switching plasmonic resonance “ON” and “OFF” of ITO-on-graphene via tuning of graphene chemical potential through electrical gating. The plasmonic resonance of ITO-on-graphene significantly enhances the field interaction with graphene which allows the size reduction compare to graphene based modulators without ITO. We presented a scheme of mode-multiplexed NIR modulator by tuning ITO permittivity as the function of carrier density through applied voltage. The wisely patterned ITO on top of an SOI ridge waveguide portrayed the independent modulation of two orthogonal modes simultaneously, which enhances functionality per-area. We proposed a theoretical model of tunable anisotropic metamaterial composed of periodic layers of graphene and Hafnium Oxide where transversal permittivity can be tuned via changing the chemical potential of graphene. A novel metamaterial assisted tunable photonic coupler is designed by inserting the proposed artificial tunable metamaterial in the coupling region of a waveguide coupler. The coupling efficiency can be tuned by changing the permittivity of metamaterial through electrical gating.
PRANAV BAHL
WOLF (machine learning WOrk fLow management Framework)When & Where:
246 Nichols Hall
Committee Members:
Luke Huan, ChairFengjun Li
Bo Luo
Abstract
Recently machine learning has been creating great strides in many areas of work field such as health, finance, education, sports etc., which has encouraged demand for machine learning systems. By definition machine learning automates the task of learning in terms of rule induction, classification, regression etc. This is then used to draw knowledgeable insights and to forecast an event before it actually takes place. Despite this automation, machine learning still does not automate the task of selecting the best algorithm(s) for a specific dataset. With the rapidly growing machine learning algorithms it has become difficult for novices as well as researchers to choose the best algorithm. The crux of a machine learning system is (1) to solve fundamental problems of preprocessing the data to help machine learning algorithm understand the data better; (2) to solve the problem of choosing meaningful features hence reducing the noise from the data; and (3) to choose the best resulting machine learning algorithm which is performed by doing grid search over hyperparameters of various machine learning algorithms and afterwards doing metric comparison amongst all outcomes. These are the problems addressed by Wolf.
Automation is the fuel that drives Wolf. Automating time-consuming and repeatable tasks are the defining characteristics of the project. The rising scope of Artificial Intelligence (AI) and machine learning increases the need for automation to simplify the process, hence help researchers and data scientists dig deeper into the problem and understand it well, rather than spending time in tweaking the algorithms. The positive correlation of growing intelligence and the complexity of solutions has shifted the trend from Artificial Intelligence (AI) to Automated Intelligence, a paradigm on which Wolf is based.
Wolf has been built to have an impact on a wider audience. The automation of machine learning pipeline saves ~40% of the work effort spent towards implementing and testing algorithm. It helps people with different levels of expertise and requirements, helps novices to identify best combinations of algorithms without having in depth knowledge of algorithms and helps researchers and businesses better their machine learning knowledge to figure out best resulting hyperparameters.
FARHAD MAHMOOD
Modeling and Analysis of Energy Efficiency in Wireless Handset Transceiver SystemsWhen & Where:
250 Nichols Hall
Committee Members:
Erik Perrins, ChairLingjia Liu
Shannon Blunt
Victor Frost
Bozenna Pasik-Duncan
Abstract
As it is becoming a significant part of our daily life, wireless mobile handsets have become faster and smarter. One of the main remaining requirement by users is to have a longer lasting wireless cellular devices. Many techniques have been used to increase the capacity of the battery (Ampere per Hour), but that increases the safety concern.
Instead, it is better to have mobile handsets that consume less energy i.e increase energy efficiency. Therefore, in this research proposal, we study and analyze the radio
frequency(RF) transceiver energy consumption, which is the largest energy consumed in the cellular device. We consider a model of large number of parameters in order to make it more realistic. First a transmitter energy of single antenna device is considered for a fixed target probability of error in the receiver for multilevel quadratic amplitude modulations (MQAM). It will be found that the power amplifier (PA) consumes the highest portion of transceiver energy due to the low efficiency of the PA.
Furthermore, when MQAM and raised cosine filter are used, the impact of peak to average ratio (PAR) on PA becomes another source of energy wasting in the PA. This issue is analyzed in this research proposal with a number of promising solutions. This analysis of energy consumption for single antenna devices will help us analyze the energy consumption of multiple antennas devices. In this regard, we discuss the energy efficiency of multiple input multiple output (MIMO) antenna with known channel state information (CSI) at the transmitter. However, the study of energy efficiency of MIMO without CSI using space time coding will be our next step.
THEODORE LINDSEY
Interesting Rule Induction Module: Adding Support for Unknown Attribute ValuesWhen & Where:
2001B Eaton Hall
Committee Members:
Jerzy Grzymala-Busse, ChairBo Luo
Prasad Kulkarni
Abstract
IRIM (Interesting Rule Induction Module) is a rule induction system designed to induce particularly strong, simple rule sets. Additionally, IRIM does not require prior discretization of numerical attribute values. IRIM does not necessarily produce consistent rules that fully describe the target concepts, however, the rules induced by IRIM often lead to novel revelations of hidden relationships in a dataset. In this paper, we attempt to extend the IRIM system to be able to handle missing attribute values (in particular, lost and do-not-care attribute values) more thoroughly than ignoring the cases that they belong to. Further, we include an implementation of IRIM in the modern programming language Python that has been written for easy inclusion in within a Python data mining package or library. The provided implementation makes use of the Pandas module which is built on top of a C back end for quick performance relative to the performance normally found with Python.