Changick Kim
2026
Generalizable Prompt Tuning for Audio-Language Models via Semantic Expansion
Jaehyuk Jang | Wonjun Lee | Kangwook Ko | Changick Kim
Findings of the Association for Computational Linguistics: ACL 2026
Jaehyuk Jang | Wonjun Lee | Kangwook Ko | Changick Kim
Findings of the Association for Computational Linguistics: ACL 2026
Prompt tuning has achieved remarkable progress in vision–language models (VLMs) and is recently being adopted for audio–language models (ALMs). However, its generalization ability in ALMs remains largely underexplored. We observe that conventional prompt tuning for ALMs also suffers from the Base–New Tradeoff, and we identify that this issue stems from the disrupted semantic structure of the embedding space. To address this issue, we propose Semantically Expanded Prompt Tuning (SEPT)—a plug-and-play framework that explicitly regularizes the prompt embedding space by incorporating semantic neighbors generated by large language models. SEPT introduces a novel semantic expansion loss with margin constraints that promote intra-class compactness and inter-class separability, thereby enhancing the semantic structure of the prompt embedding space. For comprehensive evaluation, we establish the first benchmark setup for prompt generalization in ALMs, covering both base-to-new generalization and cross-dataset transferability. Extensive experiments demonstrate that SEPT consistently improves generalization performance across multiple prompt tuning baselines, while maintaining computational cost during inference.
FinHarmBench: Financial Jailbreak Benchmark and Unsupervised Safety Fine-Tuning via Refusal Steering Distillation
Yubin Choi | Yujin Yang | Subin Kim | Seokil Ham | Seungju Cho | Jungmin Son | Youngjun Kwak | Changick Kim
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 6: Industry Track)
Yubin Choi | Yujin Yang | Subin Kim | Seokil Ham | Seungju Cho | Jungmin Son | Youngjun Kwak | Changick Kim
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 6: Industry Track)
Financial Large Language Models (LLMs) exhibit strong domain expertise but remain vulnerable to financially harmful prompts. To systematically assess this vulnerability, we introduce FinHarmBench, a benchmark designed to evaluate financially harmful and confusable benign prompts. Our analysis reveals a concerning result that financial LLMs can be less robust than general-purpose models, suggesting that domain adaptation alone does not guarantee financial safety alignment. To address this issue, we propose Financial Refusal Steering Distillation (FiRSD), an unsupervised training framework that strengthens financial-domain safety by learning and distilling a financial refusal direction at the representation level. FiRSD enhances refusal behavior without requiring annotated refusal responses. Experiments show that FiRSD substantially improves safety while largely preserving task capability. These results highlight the importance of domain-aware safety alignment for high-stakes financial applications.
2025
Don’t Miss the Forest for the Trees: Attentional Vision Calibration for Large Vision Language Models
Sangmin Woo | Donguk Kim | Jaehyuk Jang | Yubin Choi | Changick Kim
Findings of the Association for Computational Linguistics: ACL 2025
Sangmin Woo | Donguk Kim | Jaehyuk Jang | Yubin Choi | Changick Kim
Findings of the Association for Computational Linguistics: ACL 2025
Large Vision Language Models (LVLMs) demonstrate strong capabilities in visual understanding and description, yet often suffer from hallucinations, attributing incorrect or misleading features to images. We observe that LVLMs disproportionately focus on a small subset of image tokens—termed blind tokens—which are typically irrelevant to the query (e.g., background or non-object regions). We hypothesize that such attention misalignment plays a key role in generating hallucinated responses. To mitigate this issue, we propose Attentional Vision Calibration (AvisC), a test-time approach that dynamically recalibrates the influence of blind tokens without modifying the underlying attention mechanism. AvisC first identifies blind tokens by analyzing layer-wise attention distributions over image tokens, then employs a contrastive decoding strategy to balance the influence of original and blind-token-biased logits. Experiments on standard benchmarks, including POPE, MME, and AMBER, demonstrate that AvisC effectively reduces hallucinations in LVLMs.