Curriculum Vitae
aness1219@yonsei.ac.kr GitHub DBLP LinkedIn
Profile
My research focuses on enhancing the reliability and efficiency of programs with LLMs. Efficiency concerns how much computation a program needs and where its bottlenecks arise; beyond predicting complexity, I generate inputs that expose real bottlenecks so inefficiency can be verified through execution. Reliability concerns whether generated code satisfies not only the required functionality but also its input contracts; I build benchmarks that quantify this and design generation methods that raise specification satisfaction. Neither problem can be judged from the final output alone, so I take a neuro-symbolic approach in which LLMs interpret natural language while structuring and verification are delegated to deterministic rules, constraint solvers, and actual execution. I have carried out five studies around these problems, four as first author including equal contributions, moving from cost prediction (TCProF, MEC³O) to bottleneck-exposing tests (STAB), and from functional-correctness evaluation to specification-compliance evaluation (ContractEval) and improvement (SLICE). Most recently I extended the same execution-aware view to provenance: SEW watermarks already generated code through keyed code-style choices and detects them with calibrated, context-aware evidence.
Education
- Yonsei University, Seoul, Korea
Integrated M.S./Ph.D. in Computer Science
2024.03 – 2029.02 (expected) - Myongji University, Korea
B.S. in Information & Communication Engineering
2018.03 – 2024.02
Experience
Theory of Computation Lab, Yonsei University
- Graduate Researcher (2024–Present), advised by Prof. Yo-Sub Han. Leading projects on specification-driven test generation, contract-satisfying code generation, time complexity prediction, and code watermarking with LLMs.
Publications
Click an entry to see my role, the period, and a short summary.
SEW: Style-Encoded Watermarking of LLM-Generated Code arXiv Preprint 2026
First author2026.07 – 2026.09
- Task
- Embedding and detecting a watermark in already generated code for provenance tracking, without hurting functional correctness and without false detections on human-written code.
- Method
- Code style rules collected from style guides and transformation rules are applied with style choices fixed by a secret key and each program's structural context. Detection calibrates watermark evidence with style probabilities estimated from human-written code and aggregates evidence across structurally matching locations so repeated choices cannot inflate it.
- Tech
- Style-rule transformations, keyed style selection, style-preference calibration, context-aware evidence aggregation; CodeContests across three LLMs and three languages
SLICE: Specification-Level Isolation of Contract Enforcement arXiv Preprint 2026
First author2026.05 – 2026.07
- Task
- Generating code from a natural-language specification that satisfies both the functional requirements and the input contracts.
- Method
- The specification is structured as a graph to separate functional requirements from contract conditions. Candidate bodies from the functional view are ranked by executing specification examples; contract assertions are generated separately, screened by execution, and merged into the selected body.
- Tech
- Specification graph, multi-candidate LLM generation, execution-based verification, token log-probability selection
STAB: Specification-driven Testing for Algorithmic Bottlenecks arXiv Preprint 2026
Co-first author2026.02 – 2026.05
- Task
- Generating test inputs that trigger an algorithm's worst-case execution path from the natural-language specification alone, without a reference implementation.
- Method
- A Constraint Saturator computes the largest admissible input size from the variable relations and range constraints, and an Adversarial Scenario Injector injects input structures from 13 bottleneck scenarios.
- Tech
- LLM constraint interpretation, CP-SAT constraint optimization, isolated DOMjudge · Docker execution
ContractEval: A Benchmark for Evaluating Contract-Satisfying Assertions in Code Generation Findings of ACL 2026
Co-first author2025.09 – 2026.02
- Task
- Building a benchmark that tests whether generated code actually checks its input contracts (type, range, and structure constraints).
- Method
- An LLM translates reference assertions into SMT-LIB constraints, an SMT solver finds inputs that violate exactly one targeted contract, and reference-code execution keeps only tests that trigger the intended violation, yielding 364 tasks.
- Tech
- Neuro-symbolic pipeline (LLM + Z3), HumanEval+/MBPP+, execution-based test filtering
K-SpecDetox: Korean Spectral Energy-based Detection and Detoxification of Dialect Profanity KCC 2026 (Poster)
First author2026.01 – 2026.05
- Task
- Detecting profanity in Korean dialect sentences, quantifying its toxicity, and generating detoxified sentences that keep the dialect endings.
- Method
- Token log-probabilities are treated as a signal; FFT spectral energy and a sampling-discrepancy score feed an SVM detector. Toxicity is graded into three levels, level-specific prompts produce the detoxified sentence, and a spectral re-verification loop regenerates weak outputs.
- Tech
- FFT spectral analysis, SVM, dictionary-based pre-processing, LLM prompting
MEC³O: Multi-Expert Consensus for Code Time Complexity Prediction arXiv Preprint 2025
Co-first author2024.12 – 2025.02
- Task
- Predicting the time-complexity class of source code (O(1) to O(2n)).
- Method
- The best-performing LLM per complexity class is assigned as its expert with a class-specific instruction; experts exchange feedback in a structured debate, and a weighted consensus of expertise and confidence makes the final decision.
- Tech
- Multi-agent debate, expert role prompting, weighted consensus algorithm
K-ToPiC: Korean Dialect Toxicity Polishing with Curriculum Learning-based Span Detection KCC 2025 (Oral Presentation)
Co-first author2025.03 – 2025.07
- Task
- Detecting profanity spans in Korean dialect sentences and polishing only those spans while preserving the dialect style.
- Method
- A 30,457-pair standard-to-dialect dictionary applied to KOLD yields a 28,435-sentence dialect profanity dataset; span detection is trained with a span-length curriculum, and the detected span plus a masked sentence guide the LLM to soften only the necessary expressions.
- Tech
- Curriculum learning, LLM fine-tuning (polyglot-ko, kullm-polyglot), detoxification generation (gemma, Bllossom)
TCProF: Time-Complexity Prediction SSL Framework NAACL 2025 (Oral Presentation)
Co-author2024.02 – 2024.12
- Task
- Predicting the time complexity of code in a low-resource setting with few labeled examples.
- Method
- Code augmentation (loop conversion, back-translation) and a symbolic module enrich the features, and two models trained on original and augmented data exchange pseudo-labels through co-training. I handled the baseline experiments and the co-training implementation.
- Tech
- Semi-supervised learning (co-training), AST · regex symbolic analysis, code augmentation
CA-DiaL: Curriculum and Attribute-Based Learning for Korean Dialect Translation using LLMs KSC 2024 (Poster)
First author2024.08 – 2024.09
- Task
- Training an LLM translator that converts Gyeongsang dialect sentences into standard Korean.
- Method
- Training data are split into three curriculum levels by the number of dialect words per sentence, and speaker gender and age-group attributes are prepended as a header so the model learns easy sentences and speaker patterns first.
- Tech
- QLoRA fine-tuning (Solar, KoAlpaca-Polyglot, Korean-Bllossom), AI-Hub dialect corpus
* co-first authorship; † corresponding author. See the Publications page for links and BibTeX.
Skills
- Languages: Python, C
- Techniques: LLM-based code generation & verification · Neuro-symbolic pipelines (LLM + Z3) · Multi-agent debate · Execution-based testing
- Training: Self-supervised / curriculum learning · QLoRA fine-tuning
Advisor
Prof. Yo-Sub Han
Department of Computer Science, Yonsei University
Email: emmous@yonsei.ac.kr
Last updated: October 2026