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

David Felton

Optimization and Evaluation of Physical Complementary Radar Waveforms

When & Where:


Nichols Hall, Room 129 (Apollo Auditorium)

Committee Members:

Shannon Blunt, Chair
Rachel Jarvis
Patrick McCormick
James Stiles
Zsolt Talata

Abstract

The RF spectrum is a precious, finite resource with ever-increasing demand. Consequently, the mandate to be a "good spectral neighbor" is in direct conflict with the requirements for high-performance sensing where correlation error is fundamentally limited. As such, matched-filter radar performance is often sidelobe-limited with estimation error being constrained by the time-bandwidth (TB) of the collective emission. The methods developed here seek to bridge this gap between idealized radar performance and practical utility via waveform design.    

Estimation error becomes more complex when employing pulse-agility. In doing so, range-sidelobe modulation (RSM) spreads energy across Doppler, rendering traditional methods ineffective. To address this, the gradient-based complementary-FM framework was developed to produce complementary sidelobe cancellation (CSC) after coherently combining subsets within a pulse-agile emission. In contrast to the majority of complementary signals, explored via phase-coding, these Comp-FM waveform subsets achieve CSC while preserving hardware-compatibility since they are FM (though design distortion is never completely avoided). Although Comp-FM addressed practicality via hardware amenability, CSC was localized to zero-Doppler. This work expands the Comp-FM notion to a Doppler-generalized (DG) framework, extending the cancellation condition to an arbitrary span. The same framework can likewise be employed to jointly optimize an entire coherent processing interval (CPI) to minimize RSM within the radar point-spread-function (PSF), thereby generalizing the notion of complementarity and introducing the potential for cognitive operation if sufficient scattering knowledge is available a-priori.          

Sensing with a single emitter is limited by self-inflicted error alone (e.g., clutter, sidelobes), while MIMO systems must additionally contend with the cross-responses from emitters operating concurrently (e.g., simultaneously, spatially proximate, in a shared spectrum), further degrading radar sensitivity. Now, total correlation error is dictated by the overlapping TB (i.e., how coincident are the signals) and number of operating emitters, compounding difficulty to estimate if left unaddressed. As such, the determination of "orthogonal waveforms" comprises a large portion of MIMO literature, though remains a phenomenological misnomer for pulsed emissions. Here, the notion of complementary-FM is applied to a multi-emitter context in which transmitter-amenable quasi-orthogonal subsets, occupying the same spectral band, are produced via a similar gradient-based approach. To further practicalize these MIMO-Comp-FM waveform subsets, the same "DG" approach described above, addressing the otherwise-default Doppler-induced degradation of complementary signals, is applied. In doing so, Doppler-independent separability and complementarity greatly improves estimation sensitivity for multi-emitter systems. 

This MIMO-Comp-FM framework is developed for standard matched filter processing. Coupling this framework with a "DG" form of the previously explored MIMO-MiCRFt is also investigated, illustrating the added benefit of pairing optimized subsets with similarly calibrated processing. 

Each of these methods is developed to address unique and increasingly complex sources of estimation error. All approaches are initially developed and evaluated via simulated analysis where ground-truth is known. Then, despite hardware-induced distortion being unavoidable, the MIMO-Comp-FM framework is confirmed via loopback measurements to preserve the majority of CSC that was observed in simulation. Finally, open-air demonstration of each approach validates practical utility on a radar system.


Hao Xuan

Toward an Integrated Computational Framework for Metagenomics: From Sequence Alignment to Automated Knowledge Discovery

When & Where:


Nichols Hall, Room 246 (Executive Conference Room)

Committee Members:

Cuncong Zhong, Chair
Fengjun Li
Suzanne Shontz
Hongyang Sun
Liang Xu

Abstract

Metagenomic sequencing has become a central paradigm for studying complex microbial communities and their interactions with the host, with emerging applications in clinical prediction and disease modeling. In this work, we first investigate two representative application scenarios: predicting immune checkpoint inhibitor response in non-small cell lung cancer using gut microbial signatures, and characterizing host–microbiome interactions in neonatal systems. The proposed reference-free neural network captures both compositional and functional signals without reliance on reference genomes, while the neonatal study demonstrates how environmental and genetic factors reshape microbial communities and how probiotic intervention can mitigate pathogen-induced immune activation.

These studies highlight both the promise and the inherent difficulty of metagenomic analysis: transforming raw sequencing data into clinically actionable insights remains an algorithmically fragmented and computationally intensive process. This challenge arises from two key limitations: the lack of a unified algorithmic foundation for sequence alignment and the absence of systematic approaches for selecting and organizing analytical tools. Motivated by these challenges, we present a unified computational framework for metagenomic analysis that integrates complementary algorithmic and systems-level solutions.

First, to resolve fragmentation at the alignment level, we develop the Versatile Alignment Toolkit (VAT), a unified algorithmic system for biological sequence alignment across diverse applications. VAT introduces an asymmetric multi-view k-mer indexing scheme that integrates multiple seeding strategies within a single architecture and enables dynamic seed-length adjustment via longest common prefix (LCP)–based inference without re-indexing. A flexible seed-chaining mechanism further supports diverse alignment scenarios, including collinear, rearranged, and split alignments. Combined with a hardware-efficient in-register bitonic sorting algorithm and dynamic index-loading strategy, VAT achieves high efficiency and broad applicability across read mapping, homology search, and whole-genome alignment. Second, to address the challenge of tool selection and pipeline construction, we develop SNAIL, a natural language processing system for automated recognition of bioinformatics tools from large-scale and rapidly growing scientific literature. By integrating XGBoost and Transformer-based models such as SciBERT, SNAIL enables structured extraction of analytical tools and supports automated, reproducible pipeline construction.

Together, this work establishes a unified framework that is grounded in real-world applications and addresses key bottlenecks in metagenomic analysis, enabling more efficient, scalable, and clinically actionable workflows.


Pramil Paudel

Learning Without Seeing: Privacy-Preserving and Adversarial Perspectives in Lensless Imaging

When & Where:


Eaton Hall, Room 2001B

Committee Members:

Fengjun Li, Chair
Alex Bardas
Bo Luo
Cuncong Zhong
Haiyang Chao

Abstract

Conventional computer vision relies on spatially resolved, human-interpretable images, which inherently expose sensitive information and raise privacy concerns. In this study, we explore an alternative paradigm based on lensless imaging, where scenes are captured as diffraction patterns governed by the point spread function (PSF). Although unintelligible to humans, these measurements encode structured, distributed information that remains useful for computational inference. 

We propose a unified framework for privacy-preserving vision that operates directly on lensless sensor measurements by leveraging their frequency-domain and phase-encoded properties. The framework is developed along two complementary directions. First, we enable reconstruction-free inference by exploiting the intrinsic obfuscation of lensless data. We show that semantic tasks such as classification can be performed directly on diffraction patterns using models tailored to non-local, phase-scrambled representations. We further design lensless-aware architectures and integrate them into practical pipelines, including a Swin Transformer-based steganographic framework (DiffHide) for secure and imperceptible information embedding. To assess robustness, we formalize adversarial threat models and develop defenses against learning-based reconstruction attacks, particularly GAN-driven inversion. Second, we investigate the limits of privacy by studying the reconstructability of lensless measurements without explicit knowledge of the forward model. We develop learning-based reconstruction methods that approximate the inverse mapping and analyze conditions under which sensitive information can be recovered. Our results demonstrate that lensless measurements enable effective vision tasks without reconstruction, while providing a principled framework to evaluate and mitigate privacy risks. 


Sharmila Raisa

Digital Coherent Optical System: Investigation and Monitoring

When & Where:


Nichols Hall, Room 246 (Executive Conference Room)

Committee Members:

Rongqing Hui, Chair
Morteza Hashemi
Erik Perrins
Alessandro Salandrino
Jie Han

Abstract

Coherent wavelength-division multiplexed (WDM) optical fiber systems have become the primary transmission technology for high-capacity data networks, driven by the explosive bandwidth demand of cloud computing, streaming services, and large-scale artificial intelligence training infrastructure. This dissertation investigates two fundamental aspects of digital coherent fiber optic systems under the unifying theme of source and monitoring: the design of multi-wavelength optical sources compatible with high-order coherent detection, and the leveraging of fiber Kerr-effect nonlinearity at the coherent receiver to perform physical-layer link health monitoring and to assess inherent security vulnerabilities — both achieved through digital signal processing of the received complex optical field without dedicated hardware.

We begin by addressing the multi-wavelength transmitter challenge in WDM coherent systems. Existing quantum-dot, quantum-dash, and quantum-well based optical frequency comb (OFC) sources share a common limitation: individual comb line linewidths in the tens of MHz range caused by low output power levels of 1–20 mW, making them incompatible with high-order coherent detection. We demonstrate coherent system application of a single-section InGaAsP QW Fabry-Perot laser diode with greater than 120 mW optical power at the fiber pigtail and 36.14 GHz mode spacing. The high optical power per mode produces Lorentzian equivalent linewidths below 100 kHz — compatible with 16-QAM carrier phase recovery without optical phase locking. Experimental results obtained using a commercial Ciena WaveLogic-Ai coherent transceiver demonstrate 20-channel WDM transmission over 78.3 km of standard single-mode fiber with all channels below the HD-FEC threshold of 3.8 × 10⁻³ at 30 GBaud differential-coded 16-QAM, corresponding to an aggregate capacity of 2.15 Tb/s from a single laser device.

After investigating the QW Fabry-Perot laser as a multi-wavelength source for coherent WDM transmission, we leverage the coherent receiver DSP to exploit fiber Kerr-effect nonlinearity for longitudinal power profile estimation, enabling reconstruction of the signal power distribution P(z) along the full multi-span link without dedicated hardware or traffic interruption. We propose a modified enhanced regular perturbation (ERP) method that corrects two independent physical error sources of the standard RP1 least-squares baseline: the accumulated nonlinear phase rotation, and the dispersion-mediated phase-to-intensity conversion — a second bias source not addressed by prior methods. The RP1 method produces mean absolute error (MAE) that scales quadratically with span count, growing to 1.656 dB at 10 spans and 3 dBm. The modified ERP reduces this to 0.608 dB — an improvement that grows consistently with link length, confirming increasing advantage in the long-haul regime. Extension to WDM through an XPM-aware per-channel formulation achieves MAE of 0.113–0.419 dB across 150–500 km link lengths.

In addition to its role in enabling DSP-based longitudinal power profile estimation, the fiber Kerr-effect nonlinearity is shown to give rise to an inherent physical-layer security vulnerability in coherent WDM systems. We show that an eavesdropper co-tenanting a shared fiber — transmitting a continuous-wave probe at a wavelength adjacent to the legitimate signal — can capture the XPM-induced waveform at the fiber output and apply a bidirectional gated recurrent unit neural network, trained on split-step Fourier method simulation data, to reconstruct the transmitted symbol sequence without physical fiber access and without perturbing the legitimate signal. This eavesdropping mechanism is experimentally validated using a commercial Ciena WaveLogic-Ai coherent transceiver for ASK, BPSK, QPSK, and 16-QAM modulation formats at 4.26 GBaud and 8.56 GBaud over one- and two-span 75 km fiber systems, achieving zero symbol errors under high-OSNR conditions. Noise-aware training over OSNR from 20 to 60 dB maintains symbol error rate below 10⁻² for OSNR above 25–30 dB.

Together, these three contributions demonstrate that the coherent fiber optic system is a versatile physical instrument extending well beyond its role as a data transmission medium. The coherent receiver infrastructure — deployed for high-order modulation and data recovery — simultaneously enables the high-power OFC laser to serve as a practical multi-wavelength transmitter source, and provides the complex field measurement capability through which fiber Kerr-effect nonlinearity can be exploited constructively for distributed link monitoring and, as a direct consequence, reveals an inherent physical-layer security exposure in shared fiber infrastructure. This unified perspective on the coherent system as both a transmission platform and a general-purpose measurement instrument has direct relevance to the design of spectrally efficient, self-monitoring, and physically secure optical interconnects for next-generation AI computing networks.


Arman Ghasemi

Task-Oriented Data Communication and Compression for Timely Forecasting and Control in Smart Grids

When & Where:


Nichols Hall, Room 246 (Executive Conference Room)

Committee Members:

Morteza Hashemi, Chair
Alexandru Bardas
Prasad Kulkarni
Taejoon Kim
Zsolt Talata

Abstract

Advances in sensing, communication, and intelligent control have transformed power systems into data-driven smart grids, where forecasting and intelligent decision-making are essential components. Modern smart grids include distributed energy resources (DERs), renewable generation, battery energy storage systems, and large numbers of grid-edge devices that continuously generate time-series data. At the same time, increasing renewable penetration introduces substantial uncertainty in generation, net load, and market operations, while communication networks impose bandwidth, latency, and reliability constraints on timely data delivery. This dissertation addresses how time-series forecasting, data compression, and task-oriented wireless communication can be jointly designed for smart grid applications.

First, we study weather-aware distributed energy management in prosumer-centric microgrids and show that incorporating day-ahead weather information into decision-making improves battery dispatch and reduces the impact of renewable uncertainty. Second, we introduce forecasting-aware energy management in both wholesale and retail electricity markets, highlighting how renewable generation forecasting affects pricing, scheduling, and uncertainty mitigation. Third, we develop and evaluate deep learning methods for renewable generation forecasting, showing that Transformer-based models outperform recurrent baselines such as RNN and LSTM for wind and solar prediction tasks.

Building on this forecasting foundation, we develop a communication-efficient forecasting framework in which high-dimensional smart grid measurements are compressed into low-dimensional latent representations before transmission. This framework is extended into a task-oriented communication system that jointly optimizes data relevance and information timeliness, so that the receiver obtains compressed updates that remain useful for downstream forecasting tasks. Finally, we extend this framework to a distributed multi-node uplink setting, where multiple grid sensors share a bandwidth-limited channel, and develop scheduling policy that improves both the timeliness and task-relevance of received updates.


Past Defense Notices

Dates

Tanvir Hossain

Security Solutions for Zero-Trust Microelectronics Supply Chains

When & Where:


Nichols Hall, Room 246 (Executive Conference Room)

Committee Members:

Tamzidul Hoque, Chair
Drew Davidson
Prasad Kulkarni
Heechul Yun
Huijeong Kim

Abstract

Microelectronics supply chains increasingly rely on globally distributed design, fabrication, integration, and deployment processes, making traditional assumptions of trusted hardware inadequate. Security in this setting can be understood through a zero-trust microelectronics supply-chain model, in which neither manufacturing partners nor procured hardware platforms are assumed trustworthy by default. Two complementary threat scenarios are considered in the proposed research. In the first scenario, custom Integrated Circuits (ICs) fabricated through potentially untrusted foundries are examined, where design-for-security protections intended to prevent piracy, overproduction, and intellectual-property theft can themselves become vulnerable to attacks. In this scenario, hardware Trojan-assisted meta-attacks are used to show that such protections can be systematically identified and subverted by fabrication-stage adversaries. In the second scenario, commercial off-the-shelf ICs are considered from the perspective of end users and procurers, where internal design visibility is unavailable and hardware trustworthiness cannot be directly verified. For this setting, runtime-oriented protection mechanisms are developed to safeguard sensitive computation against malicious hardware behavior and side-channel leakage. Building on these two scenarios, a future research direction is outlined for side-channel-driven vulnerability discovery in off-the-shelf devices, motivated by the need to evaluate and test such platforms prior to deployment when no design information is available. The proposed direction explores gray-box security evaluation using power and electromagnetic side-channel analysis to identify anomalous behaviors and potential vulnerabilities in opaque hardware platforms. Together, these directions establish a foundation for analyzing and mitigating security risks across zero-trust microelectronics supply chains.


Krishna Chaitanya Reddy Chitta

A Dynamic Resource Management Framework and Reconfiguration Strategies for Cloud-native Bulk Synchronous Parallel Applications

When & Where:


Eaton Hall, Room 2001B

Committee Members:

Hongyang Sun, Chair
David Johnson
Sumaiya Shomaji


Abstract

Many High Performance Computing (HPC) applications following the Bulk Synchronous Parallel

(BSP) model are increasingly deployed in cloud-native, multi-tenant container environments such

as Kubernetes. Unlike dedicated HPC clusters, these shared platforms introduce resource virtualization

and variability, making BSP applications more susceptible to performance fluctuations.

Workload imbalance across supersteps can trigger the straggler effect, where faster tasks wait

at synchronization barriers for slower ones, increasing overall execution time. Existing BSP resource

management approaches typically assume static workloads and reuse a single configuration

throughout execution. However, real-world workloads vary due to dynamic data and system conditions,

making static configurations suboptimal. This limitation underscores the need for adaptive

resource management strategies that respond to workload changes while considering reconfiguration

costs.

 

To address these limitations, we evaluate a dynamic, data-driven resource management framework

tailored for cloud-native BSP applications. This approach integrates workload profiling,

time-series forecasting, and predictive performance modeling to estimate task execution behavior

under varying workload and resource conditions. The framework explicitly models the trade-off

between performance gains achieved through reconfiguration and the associated checkpointing

and migration costs incurred during container reallocation. Multiple reconfiguration strategies

are evaluated, spanning simple window-based heuristics, dynamic programming methods, and

reinforcement learning approaches. Through extensive experimental evaluation, this framework

demonstrates up to 24.5% improvement in total execution time compared to a baseline static configuration.

Furthermore, we systematically analyze the performance of each strategy under varying

workload characteristics, simulation lengths, and checkpoint penalties, and provide guidance on

selecting the most appropriate strategy for a given workload environment.


Smriti Pranjal

NoBIAS: Non-coding RNA Base Interaction Annotation using Visual Snapshot

When & Where:


Slawson Hall, Room 198

Committee Members:

Cuncong Zhong, Chair
Sumaiya Shomaji
Hongyang Sun
Zijun Yao
Xiaoqing Wu

Abstract

Non-coding RNAs fold into complex 3D structures that govern their biological functions, with RNA structural motifs (RSMs) serving as conserved building blocks of this architecture.
These motifs are defined by characteristic base-interaction patterns, making accurate identification and classification of RNA interactions essential for understanding RNA structure and function.

Despite their biological importance, accurately identifying and classifying these interactions remains challenging because the available data are highly variable in quality and scarce in quantity. This compromises annotation reliability, hinders the construction of trustworthy ground truth for systematic assessment, and restricts the supply of reliable training examples needed for supervised learning.

To address this, we introduce NoBIAS, the first resolution-aware, integrated machine learning-based suite for annotating base interactions from 3D RNA structures, inspired by human pattern recognition, augmented with structure prediction for data enrichment, and evaluated on a carefully curated, stratified benchmark.

NoBIAS is a hierarchical framework for RNA base-interaction annotation that integrates interaction-specific inductive biases with multimodal representation learning. By combining a convolution-augmented, rule-guided module for stacking interactions with complementary graph and image encoders for pairing interactions, NoBIAS captures both structural priors and local visual cues of RNA base doublets. A performance-calibrated logit fusion scheme then adaptively integrates modality-specific predictions based on local-structural resolution, enabling robust inference across heterogeneous 3D RNA structures.

Evaluation across multiple benchmark tiers: spanning consensus, homolog-supported, and manually verified cases, shows that NoBIAS consistently outperforms existing methods under increasingly challenging conditions. Together, the NoBIAS design and its evaluation framework provide a systematic foundation for robust RNA base-interaction annotation, enabling more reliable analysis of RNA structure under realistic uncertainty.


Md Mashfiq Rizvee

Hierarchical Probabilistic Architectures for Scalable Biometric and Electronic Authentication in Secure Surveillance Ecosystems

When & Where:


Eaton Hall, Room 2001B

Committee Members:

Sumaiya Shomaji, Chair
Tamzidul Hoque
David Johnson
Hongyang Sun
Alexandra Kondyli

Abstract

Secure and scalable authentication has become a primary requirement in modern digital ecosystems, where both human biometrics and electronic identities must be verified under noise, large population growth and resource constraints. Existing approaches often struggle to simultaneously provide storage efficiency, dynamic updates and strong authentication reliability. The proposed work advances a unified probabilistic framework based on Hierarchical Bloom Filter (HBF) architectures to address these limitations across biometric and hardware domains. The first contribution establishes the Dynamic Hierarchical Bloom Filter (DHBF) as a noise-tolerant and dynamically updatable authentication structure for large-scale biometrics. Unlike static Bloom-based systems that require reconstruction upon updates, DHBF supports enrollment, querying, insertion and deletion without structural rebuild. Experimental evaluation on 30,000 facial biometric templates demonstrates 100% enrollment and query accuracy, including robust acceptance of noisy biometric inputs while maintaining correct rejection of non-enrolled identities. These results validate that hierarchical probabilistic encoding can preserve both scalability and authentication reliability in practical deployments. Building on this foundation, Bio-BloomChain integrates DHBF into a blockchain-based smart contract framework to provide tamper-evident, privacy-preserving biometric lifecycle management. The system stores only hashed and non-invertible commitments on-chain while maintaining probabilistic verification logic within the contract layer. Large-scale evaluation again reports 100% enrollment, insertion, query and deletion accuracy across 30,000 templates, therefore, solving the existing problem of blockchains being able to authenticate noisy data. Moreover, the deployment analysis shows that execution on Polygon zkEVM reduces operational costs by several orders of magnitude compared to Ethereum, therefore, bringing enrollment and deletion costs below $0.001 per operation which demonstrate the feasibility of scalable blockchain biometric authentication in practice. Finally, the hierarchical probabilistic paradigm is extended to electronic hardware authentication through the Persistent Hierarchical Bloom Filter (PHBF). Applied to electronic fingerprints derived from physical unclonable functions (PUFs), PHBF demonstrates robust authentication under environmental variations such as temperature-induced noise. Experimental results show zero-error operation at the selected decision threshold and substantial system-level improvements as well as over 10^5 faster query processing and significantly reduced storage requirements compared to large scale tracking.


Fatima Al-Shaikhli

Optical Measurements Leveraging Coherent Fiber Optics Transceivers

When & Where:


Nichols Hall, Room 246 (Executive Conference Room)

Committee Members:

Rongqing Hui, Chair
Shannon Blunt
Shima Fardad
Alessandro Salandrino
Judy Wu

Abstract

Recent advancements in optical technology are invaluable in a variety of fields, extending far beyond high-speed communications. These innovations enable optical sensing, which plays a critical role across diverse applications, from medical diagnostics to infrastructure monitoring and automotive systems. This research focuses on leveraging commercially available coherent optical transceivers to develop novel measurement techniques to extract detailed information about optical fiber characteristics, as well as target information. Through this approach, we aim to enable accurate and fast assessments of fiber performance and integrity, while exploring the potential for utilizing existing optical communication networks to enhance fiber characterization capabilities. This goal is investigated through three distinct projects: (1) fiber type characterization based on intensity-modulated electrostriction response, (2) coherent Light Detection and Ranging (LiDAR) system for target range and velocity detection through different waveform design, including experimental validation of frequency modulation continuous wave (FMCW) implementations and theoretical analysis of orthogonal frequency division multiplexing (OFDM) based approaches and (3) birefringence measurements using a coherent Polarization-sensitive Optical Frequency Domain Reflectometer (P-OFDR) system.

Electrostriction in an optical fiber is introduced by interaction between the forward propagated optical signal and the acoustic standing waves in the radial direction resonating between the center of the core and the cladding circumference of the fiber. The response of electrostriction is dependent on fiber parameters, especially the mode field radius. We demonstrated a novel technique of identifying fiber types through the measurement of intensity modulation induced electrostriction response. As the spectral envelope of electrostriction induced propagation loss is anti-symmetrical, the signal to noise ratio can be significantly increased by subtracting the measured spectrum from its complex conjugate. We show that if the field distribution of the fiber propagation mode is Gaussian, the envelope of the electrostriction-induced loss spectrum closely follows a Maxwellian distribution whose shape can be specified by a single parameter determined by the mode field radius.        

We also present a self-homodyne FMCW LiDAR system based on a coherent receiver. By using the same linearly chirped waveform for both the LiDAR signal and the local oscillator, the self-homodyne coherent receiver performs frequency de-chirping directly in the photodiodes, significantly simplifying signal processing. As a result, the required receiver bandwidth is much lower than the chirping bandwidth of the signal. Simultaneous multi-target of range and velocity detection is demonstrated experimentally. Furthermore, we explore the use of commercially available coherent transceivers for joint communication and sensing using OFDM waveforms.

In addition, we demonstrate a P-OFDR system utilizing a digital coherent optical transceiver to generate a linear frequency chirp via carrier-suppressed single-sideband modulation. This method ensures linearity in chirping and phase continuity of the optical carrier. The coherent homodyne receiver, incorporating both polarization and phase diversity, recovers the state of polarization (SOP) of the backscattered optical signal along the fiber, mixing with an identically chirped local oscillator. With a spatial resolution of approximately 5 mm, a 26 GHz chirping bandwidth, and a 200 us measurement time, this system enables precise birefringence measurements. By employing three mutually orthogonal SOPs of the launched optical signal, we measure relative birefringence vectors along the fiber.


Fairuz Shadmani Shishir

Toward Trustworthy Biomedical AI: Efficient Protein Language Models and Privacy-Aware Clinical Representations

When & Where:


Nichols Hall, Room 246 (Executive Conference Room)

Committee Members:

Sumaiya Shomaji, Chair
Tamzidul Hoque
Cuncong Zhong
Bishnu Sarker
Michael Hageman

Abstract

Accurate biological sequence annotation and privacy-aware clinical modeling are central challenges in modern computational biology and biomedical AI. This dissertation presents scalable and interpretable deep learning frameworks spanning protein family classification, metal-ion binding prediction, and privacy-preserving electrocardiogram (ECG) representation learning. First, we introduce GPCR-SLM, a lightweight transformer-based framework for high-resolution classification of G-protein coupled receptors (GPCRs), one of the largest and most pharmacologically important protein families, targeted by approximately 35% of FDA-approved drugs. Unlike traditional homology-based tools such as BLAST and HMMER, which struggle to distinguish closely related families with low sequence similarity, our knowledge-distilled small language model achieves 99% accuracy across 86 GPCR families. The framework significantly outperforms BLAST (86.4%) and HMMER (91%) while delivering a 33.5× computational speedup compared to large protein language models, enabling scalable functional annotation as protein databases continue to expand. 

Second, we present an end-to-end deep learning pipeline for protein–metal-ion binding prediction. Binding site annotation is traditionally labor-intensive and limited by handcrafted features or predefined residue sets. We systematically evaluate five state-of-the-art protein language models and incorporate positional encoding to capture long-range residue dependencies. Our approach achieves a Matthews Correlation Coefficient (MCC) of 0.89 with precision, recall, and F1 scores exceeding 95% for six major metal ions under 10-fold cross-validation, demonstrating robust predictive performance and improved biological interpretability. Finally, we address fairness and privacy in clinical AI through a variational autoencoder (VAE) framework for ECG representation learning. Because ECGs inherently encode sensitive soft biometrics such as sex, age, and race, we design a dual-discriminator architecture that suppresses demographic information while preserving clinically relevant signals. The reconstructed ECGs substantially reduce demographic identifiability while maintaining strong predictive performance for reduced left ventricular ejection fraction, left ventricular hypertrophy, and 5-year mortality. 

Collectively, this work advances parameter-efficient, scalable, and privacy-conscious deep learning methodologies for both molecular and clinical domains, bridging computational protein science and trustworthy biomedical AI. 


Shailesh Pandey

Vision-Based Motor Assessment in Autism: Deep Learning Methods for Detection, Classification, and Tracking

When & Where:


Zoom defense, please email jgrisafe@ku.edu for defense information

Committee Members:

Sumaiya Shomaji, Chair
Shima Fardad
Zijun Yao
Cuncong Zhong
Lisa Dieker

Abstract

Motor difficulties show up in as many as 90% of people with autism, but surprisingly few, somewhere between 13% and 32%, ever get motor-focused help. A big part of the problem is that the tools we have for measuring motor skills either rely on a clinician's subjective judgment or require expensive lab equipment that most families will never have access to. This dissertation tries to close that gap with three projects, all built around the idea that a regular webcam and some well-designed deep learning models can do much of what costly motion-capture labs do today.

The first project asks a straightforward question: can a computer tell the difference between how someone with autism moves and how a typically developing person moves, just by watching a short video? The answer, it turns out, is yes. We built an ensemble of three neural networks, each one tuned to notice something different. One focuses on how joints coordinate with each other spatially, other zeroes in on the timing of movements, and the third learns which body-part relationships matter most for a given clip. We tested the system on 582 videos from 118 people (69 with ASD and 49 without) performing simple everyday actions like stirring or hammering. The ensemble correctly classifies 95.65% of cases. The timing-focused model on its own hits 92%, which is nearly 10 points better than a standard recurrent network baseline. And when all three models agree, accuracy climbs above 98%.

The second project deals with stimming, the repetitive behaviors like arm flapping, head banging, and spinning that are common in autism. Working with 302 publicly available videos, we trained a skeleton-based model that reaches 91% accuracy using body pose alone. That is more than double the 47% that previous work managed on the same benchmark. When we combine the pose information with what the raw video shows through a late fusion approach, accuracy jumps to 99.9%. Across the entire test set, only a single video was misclassified.

The third project is E-MotionSpec, a web platform designed for clinicians and researchers who want to track motor development over time. It runs in any browser, uses MediaPipe to estimate body pose in real time, and extracts 44 movement features grouped into seven domains covering things like how smoothly someone moves, how quickly they initiate actions, and how coordinated their limbs are. We validated the platform on the same 118-participant dataset and found 36 features with statistically significant differences between the ASD and typically developing groups. Smoothness and initiation timing stood out as the strongest discriminators. The platform also includes tools for comparing sessions over time using frequency analysis and dynamic time warping, so a clinician can actually see whether someone's motor patterns are changing across weeks or months.

Taken together, these three projects offer a practical path toward earlier identification and better ongoing monitoring of motor difficulties in autism. Everything runs on a webcam and a web browser. No motion-capture suits, no force plates, no specialized labs. That matters most for the families, schools, and clinics that need these tools the most and can least afford the alternatives.


Md Abu Saeed

Comparative Analysis of Deep Learning Models for Guava Leaf Disease Diagnosis

When & Where:


Eaton Hall, Room 2001B

Committee Members:

Sumaiya Shomaji, Chair
David Johnson
Hongyang Sun


Abstract

Guava leaf diseases significantly affect crop yield and quality, making timely detection essential for effective disease management. This project presents an end-to-end software system for automated guava leaf disease detection using deep learning and transfer learning techniques. Multiple pretrained convolutional neural network (CNN) architectures, including ResNet, AlexNet, VGG, SqueezeNet, DenseNet, Inception-v3, and EfficientNet, were adapted through feature extraction and trained on a guava leaf image dataset.

The system allows users to either capture an image using a camera or upload an existing leaf image through a software interface. The input image is processed and classified by the trained deep learning model, and the predicted disease class is displayed to the user. The dataset was divided into training, validation, and test sets to ensure robust performance evaluation, and final test accuracy was used to measure generalization on unseen data.

Experimental results demonstrate that transfer learning enables accurate and efficient guava leaf disease classification. Among the evaluated models, the best-performing architecture achieved an accuracy between 97% to 99%. Overall, the developed software provides a practical and user-friendly solution for real-world agricultural disease diagnosis.


Zhaohui Wang

Detection and Mitigation of Cross-App Privacy Leakage and Interaction Threats in IoT Automation

When & Where:


Nichols Hall, Room 250 (Gemini Conference Room)

Committee Members:

Fengjun Li, Chair
Alex Bardas
Drew Davidson
Bo Luo
Haiyang Chao

Abstract

The rapid growth of Internet of Things (IoT) technology has brought unprecedented convenience to everyday life, enabling users to deploy automation rules and develop IoT apps tailored to their specific needs. However, modern IoT ecosystems consist of numerous devices, applications, and platforms that interact continuously. As a result, users are increasingly exposed to complex and subtle security and privacy risks that are difficult to fully comprehend. Even interactions among seemingly harmless apps can introduce unforeseen security and privacy threats. In addition, violations of memory integrity can undermine the security guarantees on which IoT apps rely.

The first approach investigates hidden cross-app privacy leakage risks in IoT apps. These risks arise from cross-app interaction chains formed among multiple seemingly benign IoT apps. Our analysis reveals that interactions between apps can expose sensitive information such as user identity, location, tracking data, and activity patterns. We quantify these privacy leaks by assigning probability scores to evaluate risk levels based on inferences. In addition, we provide a fine-grained categorization of privacy threats to generate detailed alerts, enabling users to better understand and address specific privacy risks.

The second approach addresses cross-app interaction threats in IoT automation systems by leveraging a logic-based analysis model grounded in event relations. We formalize event relationships, detect event interferences, and classify rule conflicts, then generate risk scores and conflict rankings to enable comprehensive conflict detection and risk assessment. To mitigate the identified interaction threats, an optimization-based approach is employed to reduce risks while preserving system functionality. This approach ensures comprehensive coverage of cross-app interaction threats and provides a robust solution for detecting and resolving rule conflicts in IoT environments.

To support the development and rigorous evaluation of these security analyses, we further developed a large-scale, manually verified, and comprehensive dataset of real-world IoT apps. This clean and diverse benchmark dataset supports the development and validation of IoT security and privacy solutions. All proposed approaches are evaluated using this dataset of real-world apps, collectively offering valuable insights and practical tools for enhancing IoT security and privacy against cross-app threats. Furthermore, we examine the integrity of the execution environment that supports IoT apps. We show that, even under non-privileged execution, carefully crafted memory access patterns can induce bit flips in physical memory, allowing attackers to corrupt data and compromise system integrity without requiring elevated privileges.


Shawn Robertson

A Low-Power Low-Throughput Communications Solution for At-Risk Populations in Resource Constrained Contested Environments

When & Where:


Nichols Hall, Room 246 (Executive Conference Room)

Committee Members:

Alex Bardas, Chair
Drew Davidson
Fengjun Li
Bo Luo
Shawn Keshmiri

Abstract

In resource‑constrained contested environments (RCCEs), communications are routinely censored, surveilled, or disrupted by nation‑state adversaries, leaving at‑risk populations—including protesters, dissidents, disaster‑affected communities, and military units—without secure connectivity. This dissertation introduces MeshBLanket, a Bluetooth Mesh‑based framework designed for low‑power, low‑throughput messaging with minimal electromagnetic spectrum exposure. Built on commercial off‑the‑shelf hardware, MeshBLanket extends the Bluetooth Mesh specification with automated provisioning and network‑wide key refresh to enhance scalability and resilience.

We evaluated MeshBLanket through field experimentation (range, throughput, battery life, and security enhancements) and qualitative interviews with ten senior U.S. Army communications experts. Thematic analysis revealed priorities of availability, EMS footprint reduction, and simplicity of use, alongside adoption challenges and institutional skepticism. Results demonstrate that MeshBLanket maintains secure messaging under load, supports autonomous key refresh, and offers operational relevance at the forward edge of battlefields.

Beyond military contexts, parallels with protest environments highlight MeshBLanket’s broader applicability for civilian populations facing censorship and surveillance. By unifying technical experimentation with expert perspectives, this work contributes a proof‑of‑concept communications architecture that advances secure, resilient, and user‑centric connectivity in environments where traditional infrastructure is compromised or weaponized.