J. Yang
Please Note
73 records found
1
This thesis presents a framework that transforms a standard CNN into a communication-efficient distributed execution across a cluster of networked MCUs. An offline stage quantizes the model to an 8-bit integer and compiles it into a communication-aware execution plan and per-worker manifests. An online stage executes the plan on a coordinator–worker cluster. There are two novel mechanisms in the system: block-wise local execution, which keeps each expanded activation inside a worker, and cross-block data reuse, which exchanges only the thin boundary rows between consecutive blocks.
We implement the framework on a network of six MCUs and evaluate it on four representative IRB-based CNNs. Compared with naive layer-wise execution, our framework reduces early-block communication overhead by over 80%, end-to-end inference latency by up to 47%, and coordinator peak SRAM from 735 KB to 158 KB. ...
This thesis presents a framework that transforms a standard CNN into a communication-efficient distributed execution across a cluster of networked MCUs. An offline stage quantizes the model to an 8-bit integer and compiles it into a communication-aware execution plan and per-worker manifests. An online stage executes the plan on a coordinator–worker cluster. There are two novel mechanisms in the system: block-wise local execution, which keeps each expanded activation inside a worker, and cross-block data reuse, which exchanges only the thin boundary rows between consecutive blocks.
We implement the framework on a network of six MCUs and evaluate it on four representative IRB-based CNNs. Compared with naive layer-wise execution, our framework reduces early-block communication overhead by over 80%, end-to-end inference latency by up to 47%, and coordinator peak SRAM from 735 KB to 158 KB.
Proactive Code Refactoring with Agentic Workflows
How Far Are We?
The proposed pipeline uses stacked prediction models to detect candidate Java refactoring opportunities and then applies large language model-based components to assess, select, and generate patches for plausible operations. The workflow was implemented in an IntelliJ IDEA plugin. The system was evaluated on 2,000 real-world Java examples created after the training cutoff of the evaluated models, using Qwen2.5-Coder models of 7B, 14B, and 32B parameters. In addition, 12 developers evaluated the plugin in a 2x2 crossover study.
The results show that large language models can improve metric-based refactoring prediction mainly as selective filters, reducing false positives and supporting reviewable suggestions. However, this filtering introduces a precision-recall trade-off, and candidate reranking still remains an open problem. The 14B model produced the strongest candidate lists for developer review, while the 32B model was more selective and the 7B model was faster but less stable.
This thesis shows that large language models can improve automated refactoring support when used in a human-in-the-loop IDE workflow. The strongest use case being reviewable, developer-controlled assistance. Future work should address broader refactoring coverage, multi-label prediction, better datasets, and edit-history-based techniques for faster in-IDE suggestions. ...
The proposed pipeline uses stacked prediction models to detect candidate Java refactoring opportunities and then applies large language model-based components to assess, select, and generate patches for plausible operations. The workflow was implemented in an IntelliJ IDEA plugin. The system was evaluated on 2,000 real-world Java examples created after the training cutoff of the evaluated models, using Qwen2.5-Coder models of 7B, 14B, and 32B parameters. In addition, 12 developers evaluated the plugin in a 2x2 crossover study.
The results show that large language models can improve metric-based refactoring prediction mainly as selective filters, reducing false positives and supporting reviewable suggestions. However, this filtering introduces a precision-recall trade-off, and candidate reranking still remains an open problem. The 14B model produced the strongest candidate lists for developer review, while the 32B model was more selective and the 7B model was faster but less stable.
This thesis shows that large language models can improve automated refactoring support when used in a human-in-the-loop IDE workflow. The strongest use case being reviewable, developer-controlled assistance. Future work should address broader refactoring coverage, multi-label prediction, better datasets, and edit-history-based techniques for faster in-IDE suggestions.
This work studies the robustness of coding agents to metamorphic transformations applied across the repository. We use three behavior-preserving transformations that rename identifiers, restructure control flow, and reorder methods. We transform 25 instances from the SWE-rebench-V2 dataset and run Claude Code and Codex on both the original and transformed versions.
The results show that coding agents appear more robust than standalone LLMs. Still, both agents tend to explore the codebase more in the transformed version. For Claude Code, we see an increase in the success rate, while Codex shows greater run-to-run variability in the input tokens, making it less predictable. We read these trends as evidence that the agents are relying less on memorized patterns and more on freshly-read code. Still, this tendency toward robustness should be considered a practical observation, not definitive proof. The run-to-run variance of the agents is large, often larger than the effect we look for, so we can only show we don't see a difference, but cannot prove there is none. So, to answer the question in our title: in practice, most likely robust. ...
This work studies the robustness of coding agents to metamorphic transformations applied across the repository. We use three behavior-preserving transformations that rename identifiers, restructure control flow, and reorder methods. We transform 25 instances from the SWE-rebench-V2 dataset and run Claude Code and Codex on both the original and transformed versions.
The results show that coding agents appear more robust than standalone LLMs. Still, both agents tend to explore the codebase more in the transformed version. For Claude Code, we see an increase in the success rate, while Codex shows greater run-to-run variability in the input tokens, making it less predictable. We read these trends as evidence that the agents are relying less on memorized patterns and more on freshly-read code. Still, this tendency toward robustness should be considered a practical observation, not definitive proof. The run-to-run variance of the agents is large, often larger than the effect we look for, so we can only show we don't see a difference, but cannot prove there is none. So, to answer the question in our title: in practice, most likely robust.
LLM-Orchestrated Iterative Retrieval for Contract Clause Extraction
A Controlled Study on CUAD
in documents that can span hundreds of pages, and errors in this task
carry direct legal consequences.
Standard retrieve-and-extract pipelines reduce hallucination by grounding
language model outputs in retrieved document text, but their single
retrieval step cannot follow cross-references, check whether the gathered
evidence is complete, or reliably confirm that a clause is absent.
Whether having a language model actively direct each retrieval step,
rather than passively reading a fixed set of retrieved chunks, improves
clause extraction accuracy has not, to the best of our knowledge,
been tested.
This thesis provides a controlled comparison of retrieve-and-extract
and LLM-orchestrated iterative retrieval on the Contract Understanding
Atticus Dataset (CUAD), keeping all components except the retrieval
architecture constant and evaluating both systems across all 38 clause
categories under Exact Match, token-level F1, and ROUGE-L.
Iterative retrieval consistently outperforms single-pass retrieval.
The main experiment, a 5427-pair run on Gemma4~e4b, a 4-billion-parameter
model run locally via Ollama, improves Exact Match from 0.687 to 0.744, Token
F1 from 0.341 to 0.505, and ROUGE-L from 0.308 to 0.467, with every gain
statistically significant under paired tests.
A smaller balanced run on both models confirms this and shows the gain again on
the larger closed model GPT-5-mini, which improves from Exact Match 0.711 to
0.800, Token F1 0.314 to 0.538, and ROUGE-L 0.283 to 0.490.
The F1 gains substantially exceed the Exact Match gains in every case,
indicating that iterative retrieval improves the completeness of
extracted clause text, not only presence-or-absence decisions.
The comparison isolates the contribution of LLM involvement at the
retrieval step in a domain and evaluation setting where, to the best
of our knowledge, it has not previously been measured. ...
in documents that can span hundreds of pages, and errors in this task
carry direct legal consequences.
Standard retrieve-and-extract pipelines reduce hallucination by grounding
language model outputs in retrieved document text, but their single
retrieval step cannot follow cross-references, check whether the gathered
evidence is complete, or reliably confirm that a clause is absent.
Whether having a language model actively direct each retrieval step,
rather than passively reading a fixed set of retrieved chunks, improves
clause extraction accuracy has not, to the best of our knowledge,
been tested.
This thesis provides a controlled comparison of retrieve-and-extract
and LLM-orchestrated iterative retrieval on the Contract Understanding
Atticus Dataset (CUAD), keeping all components except the retrieval
architecture constant and evaluating both systems across all 38 clause
categories under Exact Match, token-level F1, and ROUGE-L.
Iterative retrieval consistently outperforms single-pass retrieval.
The main experiment, a 5427-pair run on Gemma4~e4b, a 4-billion-parameter
model run locally via Ollama, improves Exact Match from 0.687 to 0.744, Token
F1 from 0.341 to 0.505, and ROUGE-L from 0.308 to 0.467, with every gain
statistically significant under paired tests.
A smaller balanced run on both models confirms this and shows the gain again on
the larger closed model GPT-5-mini, which improves from Exact Match 0.711 to
0.800, Token F1 0.314 to 0.538, and ROUGE-L 0.283 to 0.490.
The F1 gains substantially exceed the Exact Match gains in every case,
indicating that iterative retrieval improves the completeness of
extracted clause text, not only presence-or-absence decisions.
The comparison isolates the contribution of LLM involvement at the
retrieval step in a domain and evaluation setting where, to the best
of our knowledge, it has not previously been measured.
With Great Power Comes Great Responsibility
A Tool for Energy-Aware Java Development
This thesis presents a manifest-guided deployment framework that decouples the precision policy from firmware execution. An offline packer turns a trained INT8 model and its per-tensor precision plan into a packed FlatBuffer plus a precision manifest, so one unchanged firmware serves different sub-byte policies. On the device, a two-phase Prepare/Eval contract routes each packed tensor to a backend path that keeps weight unpacking off the multiply-accumulate loop, trading a little SRAM for INT8-level latency. We implement the framework in TensorFlow Lite Micro and evaluate it on an Arm Cortex-M33 across five models and three sensing modalities. It reduces model Flash by 31% to 50% and keeps INT4, INT2, and mixed-precision inference within 0.91× to 1.24× of INT8 latency, recovering near-INT8 execution speed while retaining the storage savings of sub-byte weights. ...
This thesis presents a manifest-guided deployment framework that decouples the precision policy from firmware execution. An offline packer turns a trained INT8 model and its per-tensor precision plan into a packed FlatBuffer plus a precision manifest, so one unchanged firmware serves different sub-byte policies. On the device, a two-phase Prepare/Eval contract routes each packed tensor to a backend path that keeps weight unpacking off the multiply-accumulate loop, trading a little SRAM for INT8-level latency. We implement the framework in TensorFlow Lite Micro and evaluate it on an Arm Cortex-M33 across five models and three sensing modalities. It reduces model Flash by 31% to 50% and keeps INT4, INT2, and mixed-precision inference within 0.91× to 1.24× of INT8 latency, recovering near-INT8 execution speed while retaining the storage savings of sub-byte weights.
This thesis investigates whether Large Language Models (LLMs) can assist in augmenting existing DDFs using information extracted from historical APs. More specifically, the work focuses on how to generate additional diagnostic questions and failure modes from free-form diagnostic descriptions. Due to confidentiality constraints and realistic industrial deployment requirements, the study evaluates compact open-weight instruction-tuned language models that can be executed locally.
A central challenge in this task is evaluation. Unlike many traditional natural language processing tasks, there is often no single correct diagnostic question or failure mode for a given situation. As a result, standard reference-based evaluation metrics may fail to accurately reflect the practical usefulness of generated outputs. This thesis therefore investigates both automatic and human-centered evaluation strategies for open-ended diagnostic generation.
Four compact LLMs are evaluated using a dataset constructed from historical APs and corresponding DDF updates. Automatic evaluation is performed using semantic similarity metrics, including BERTScore. In addition, human evaluation is conducted through pairwise comparison experiments, where annotators compare outputs generated by different models for the same diagnostic scenario.
The results show that embedding-based automatic metrics provide useful signals regarding semantic similarity, but do not fully capture the practical quality and diagnostic usefulness of generated outputs. Human evaluation reveals substantial disagreement in the task, with annotators frequently preferring different outputs or judging outputs to be similarly useful. These findings highlight the difficulty of evaluating open-ended diagnostic reasoning tasks using purely automatic methods.
This work contributes to the growing body of research on industrial applications of LLMs by positioning DDF augmentation as diagnostic process repair and by exposing a central methodological gap that emerges under a reference-update operationalization: similarity to historical updates can be measured automatically, but it does not fully explain human preferences or perceived usefulness. These findings indicate that evaluation and validation, rather than generation alone, remain major obstacles to deploying LLM support in practice.
...
This thesis investigates whether Large Language Models (LLMs) can assist in augmenting existing DDFs using information extracted from historical APs. More specifically, the work focuses on how to generate additional diagnostic questions and failure modes from free-form diagnostic descriptions. Due to confidentiality constraints and realistic industrial deployment requirements, the study evaluates compact open-weight instruction-tuned language models that can be executed locally.
A central challenge in this task is evaluation. Unlike many traditional natural language processing tasks, there is often no single correct diagnostic question or failure mode for a given situation. As a result, standard reference-based evaluation metrics may fail to accurately reflect the practical usefulness of generated outputs. This thesis therefore investigates both automatic and human-centered evaluation strategies for open-ended diagnostic generation.
Four compact LLMs are evaluated using a dataset constructed from historical APs and corresponding DDF updates. Automatic evaluation is performed using semantic similarity metrics, including BERTScore. In addition, human evaluation is conducted through pairwise comparison experiments, where annotators compare outputs generated by different models for the same diagnostic scenario.
The results show that embedding-based automatic metrics provide useful signals regarding semantic similarity, but do not fully capture the practical quality and diagnostic usefulness of generated outputs. Human evaluation reveals substantial disagreement in the task, with annotators frequently preferring different outputs or judging outputs to be similarly useful. These findings highlight the difficulty of evaluating open-ended diagnostic reasoning tasks using purely automatic methods.
This work contributes to the growing body of research on industrial applications of LLMs by positioning DDF augmentation as diagnostic process repair and by exposing a central methodological gap that emerges under a reference-update operationalization: similarity to historical updates can be measured automatically, but it does not fully explain human preferences or perceived usefulness. These findings indicate that evaluation and validation, rather than generation alone, remain major obstacles to deploying LLM support in practice.
This project addresses the clinical challenges of Mechanical Thrombectomy for Acute Ischemic Stroke by optimizing the intraoperative imaging workflow. Currently, interventionists must rely on a trial-and-error process during Digital Subtraction Angiography to find the best imaging angle, which frequently leads to vessel foreshortening or overshadowing while increasing the patient's exposure to radiation and nephrotoxic contrast agents. To streamline this procedure, the project proposes a DRR-Guided Angulation approach that leverages pre-operative CTA scans to generate Digitally Reconstructed Radiographs. This method allows for the identification of optimal C-arm orientations before the procedure begins, ultimately aiming to reduce surgical time and improve the visualization of complex 3D vascular anatomy. ...
This project addresses the clinical challenges of Mechanical Thrombectomy for Acute Ischemic Stroke by optimizing the intraoperative imaging workflow. Currently, interventionists must rely on a trial-and-error process during Digital Subtraction Angiography to find the best imaging angle, which frequently leads to vessel foreshortening or overshadowing while increasing the patient's exposure to radiation and nephrotoxic contrast agents. To streamline this procedure, the project proposes a DRR-Guided Angulation approach that leverages pre-operative CTA scans to generate Digitally Reconstructed Radiographs. This method allows for the identification of optimal C-arm orientations before the procedure begins, ultimately aiming to reduce surgical time and improve the visualization of complex 3D vascular anatomy.
LLM routing aims to reduce the usage of more complex models by routing easier tasks to smaller models. However, existing research on routing primarily focuses on monetary savings and the potential for routing from a sustainability perspective has yet to be explored.
In this thesis we propose an energy-aware LLM routing framework to measure, train and evaluate various routers. We implement our framework and conduct experiments to quantify the energy efficiency of routing and to examine the trade-offs between accuracy and energy consumption. Furthermore, we analyze the overhead introduced by the various routing components. Our results show that routing can reduce energy consumption by up to 15.3\% on the HumanEval and MBPP dataset with minimal overhead when compared to a interpolated baseline. However, overall energy savings were found to decrease significantly as we aim for accuracy targets near the stronger model. These findings show that LLM routing is a viable strategy to reduce energy consumption of LLM code generation in scenarios where achieving maximum performance is not crucial. ...
LLM routing aims to reduce the usage of more complex models by routing easier tasks to smaller models. However, existing research on routing primarily focuses on monetary savings and the potential for routing from a sustainability perspective has yet to be explored.
In this thesis we propose an energy-aware LLM routing framework to measure, train and evaluate various routers. We implement our framework and conduct experiments to quantify the energy efficiency of routing and to examine the trade-offs between accuracy and energy consumption. Furthermore, we analyze the overhead introduced by the various routing components. Our results show that routing can reduce energy consumption by up to 15.3\% on the HumanEval and MBPP dataset with minimal overhead when compared to a interpolated baseline. However, overall energy savings were found to decrease significantly as we aim for accuracy targets near the stronger model. These findings show that LLM routing is a viable strategy to reduce energy consumption of LLM code generation in scenarios where achieving maximum performance is not crucial.
Training-Free Personalisation of LLMs
Representation Engineering for Per-User Toxicity Steering on PRISM
Our experiments demonstrate that parameter-efficient fine-tuning, particularly LoRA with carefully selected adapter ranks, achieves strong performance across reasoning and non-reasoning regimes while maintaining low computational cost. Explicit reasoning supervision is not required for high repair accuracy, but it significantly reduces reasoning trace lengths and inference costs. Dataset diversity and multi-turn trajectories are key to improving generalization and bridging the gap between reasoning and non-reasoning inference. Finally, this study seeks to provide empirical insights into the practical adaptation of SLMs for repository-specific APR, evaluating how strategic choices in dataset design, lightweight fine-tuning approaches, and reasoning supervision influence performance in real-world contexts. ...
Our experiments demonstrate that parameter-efficient fine-tuning, particularly LoRA with carefully selected adapter ranks, achieves strong performance across reasoning and non-reasoning regimes while maintaining low computational cost. Explicit reasoning supervision is not required for high repair accuracy, but it significantly reduces reasoning trace lengths and inference costs. Dataset diversity and multi-turn trajectories are key to improving generalization and bridging the gap between reasoning and non-reasoning inference. Finally, this study seeks to provide empirical insights into the practical adaptation of SLMs for repository-specific APR, evaluating how strategic choices in dataset design, lightweight fine-tuning approaches, and reasoning supervision influence performance in real-world contexts.
This thesis presents methods for energy-aware on-device learning on MCUs. It leverages the principle of updating specific layers of a CNN, proposed in past works, to fit memory constraints. We propose an energy-accuracy trade-off objective based on computational costs (in MACs) and accuracy improvement to select which layers to train. Furthermore, we demonstrate how computationally light search algorithms can adequately maximize the newly defined objective for layer selection. Evaluations show that our approach saves up to 200mJ of energy on-device while yielding simulation accuracies similar to a recent study under the same conditions. ...
This thesis presents methods for energy-aware on-device learning on MCUs. It leverages the principle of updating specific layers of a CNN, proposed in past works, to fit memory constraints. We propose an energy-accuracy trade-off objective based on computational costs (in MACs) and accuracy improvement to select which layers to train. Furthermore, we demonstrate how computationally light search algorithms can adequately maximize the newly defined objective for layer selection. Evaluations show that our approach saves up to 200mJ of energy on-device while yielding simulation accuracies similar to a recent study under the same conditions.
Annotation Practices in Societally Impactful Machine Learning Applications
What are these automated systems actually trained on?
Predicting CMV Serostatus using Donor Data
Leveraging a Global Database of 8 Million Donors to Predict CMV Serostatus and Investigate HLA Associations