Hoan-Suk Choi
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Hoan-Suk Choi has a total of 28 co-authors. Here are the top co-authors by number of shared publications:
- Jinhong Yang
Department of Healthcare and Information Technology, Inje University, Gimhae, Republic of Korea
7 shared publications - Nam-Hyun Yoo
Department of Computer Engineering, Kyungnam University, Changwon, Republic of Korea
4 shared publications Woo-Seop Rhee
4 shared publications- Woo-Seop Rhee
Department of Multimedia Engineering, Hanbat National University, Daejeon 34158, Korea
3 shared publications - Hung Viet Nguyen
Department of Digital Anti-Aging Healthcare, Inje University, Gimhae, Republic of Korea
2 shared publications - Beomseok Kim
Department of Medical IT, Inje University, Gimhae, South Korea
1 shared publication
Latest Publications
- Open Access
- 1 April 2026
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Access
- Vol. 14, 56652-56664
Program-Verifiable Evaluation for Temporal QA: Metrics for Evidence Validity
Time-sensitive question answering (QA) requires that the cited evidence be temporally valid at query time. However, existing evaluations focus on answer correctness while overlooking evidence timeliness. We presented a program-verifiable evaluation framework that explicitly decouples answer correctness from temporal validity. Our oracle-answer diagnostic fixes answers (Acc=1.0) while measuring evidence validity, revealing that even perfect answers cite temporally invalid documents 11.8% of the time (TMR=0.118), yielding RAS=0.903 under distance-based decay. We introduced time-consistency metrics (RAS, RAR, TMR) and evaluated on TimeFact-CEO (synthetic, N=4,793) and Wikidata-CEO (semi-structured, N=1,493). A lightweight lexico-temporal reranker improves the temporal validity rate (RAR) from 48.2% to 88.2% (+40.0pp) under an oracle-answer evaluation. Error analysis showed that the retrieval coverage (76.3% at K=3)was the primary bottleneck.We demonstrate the framework in a CEO-tenure setting where validity intervals are explicit and uniquely verifiable. Applying it to other domains is feasible when comparable interval metadata are available, and we treat cross-domain validation in future work.
- 1 April 2026
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Access
- Vol. 14, 56652-56664
Open AccessProgram-Verifiable Evaluation for Temporal QA: Metrics for Evidence Validity
Time-sensitive question answering (QA) requires that the cited evidence be temporally valid at query time. However, existing evaluations focus on answer correctness while overlooking evidence timeliness. We presented a program-verifiable evaluation framework that explicitly decouples answer correctness from temporal validity. Our oracle-answer diagnostic fixes answers (Acc=1.0) while measuring evidence validity, revealing that even perfect answers cite temporally invalid documents 11.8% of the time (TMR=0.118), yielding RAS=0.903 under distance-based decay. We introduced time-consistency metrics (RAS, RAR, TMR) and evaluated on TimeFact-CEO (synthetic, N=4,793) and Wikidata-CEO (semi-structured, N=1,493). A lightweight lexico-temporal reranker improves the temporal validity rate (RAR) from 48.2% to 88.2% (+40.0pp) under an oracle-answer evaluation. Error analysis showed that the retrieval coverage (76.3% at K=3)was the primary bottleneck.We demonstrate the framework in a CEO-tenure setting where validity intervals are explicit and uniquely verifiable. Applying it to other domains is feasible when comparable interval metadata are available, and we treat cross-domain validation in future work.
- Open Access
- 5 March 2026
- Published by Association for Computing Machinery (ACM)
- p. 217-224
Context-Enhanced Long-Term Memory System for Personalized Conversational AI: SALSA Filtering and Hybrid Retrieval Mechanism
- 5 March 2026
- Published by Association for Computing Machinery (ACM)
- p. 217-224
Open AccessContext-Enhanced Long-Term Memory System for Personalized Conversational AI: SALSA Filtering and Hybrid Retrieval Mechanism
- Open Access
- 5 March 2026
- Published by Association for Computing Machinery (ACM)
- p. 49-54
A Diffusion–Corrector Framework (PGDE–PIC) for Solving Physics-Constrained PDEs
- 5 March 2026
- Published by Association for Computing Machinery (ACM)
- p. 49-54
Open AccessA Diffusion–Corrector Framework (PGDE–PIC) for Solving Physics-Constrained PDEs
- Open Access
- 5 March 2026
- Published by Association for Computing Machinery (ACM)
- p. 403-408
Defect Detection and Automated Inspection Reporting in LNG Tank Manufacturing Using Fine-Tuned Large Vision-Language Model
- 5 March 2026
- Published by Association for Computing Machinery (ACM)
- p. 403-408
Open AccessDefect Detection and Automated Inspection Reporting in LNG Tank Manufacturing Using Fine-Tuned Large Vision-Language Model
- Open Access
- 9 May 2025
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Access
- Vol. 13, 84954-84965
High-Performance Lung Disease Identification and Explanation Using a ReciproCAM-Enhanced Lightweight Convolutional Neural Network
Lung diseases significantly contribute to global morbidity and mortality, underscoring the importance of accurate and efficient diagnostic tools. This study introduces a lightweight two-dimensional convolutional neural network (LW-2DCNN) integrated with ReciproCAM, an explainable artificial intelligence (XAI) technique, specifically designed to classify multiple pulmonary conditions from chest computed tomography (CT) scans. Our model effectively addresses limitations of existing diagnostic methods by enhancing computational efficiency, diagnostic accuracy, and interpretability. Utilizing a curated dataset comprising 10,000 CT images from a Korean population, the LW-2DCNN achieved exceptional accuracy of 99.80% across five diagnostic categories: normal, lung cancer, pneumothorax, pneumonia, and interstitial lung disease (ILD). Comparative analyses demonstrated superior performance relative to established benchmark models, including EfficientNetB0, ResNet50, InceptionV3, DenseNet121, NASNetMobile, MobileNetV2, and Xception. The integrated ReciproCAM technique significantly enhanced clinical interpretability by highlighting the precise anatomical regions influencing the model’s diagnostic decisions. Ablation studies validated the optimal choice of the Adam optimizer and demonstrated the model’s computational feasibility, predicting and explaining 1000 images in approximately 150 seconds on a CPU-only device. This indicates strong potential for deployment in resource-constrained clinical settings.
- 9 May 2025
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Access
- Vol. 13, 84954-84965
Open AccessHigh-Performance Lung Disease Identification and Explanation Using a ReciproCAM-Enhanced Lightweight Convolutional Neural Network
Lung diseases significantly contribute to global morbidity and mortality, underscoring the importance of accurate and efficient diagnostic tools. This study introduces a lightweight two-dimensional convolutional neural network (LW-2DCNN) integrated with ReciproCAM, an explainable artificial intelligence (XAI) technique, specifically designed to classify multiple pulmonary conditions from chest computed tomography (CT) scans. Our model effectively addresses limitations of existing diagnostic methods by enhancing computational efficiency, diagnostic accuracy, and interpretability. Utilizing a curated dataset comprising 10,000 CT images from a Korean population, the LW-2DCNN achieved exceptional accuracy of 99.80% across five diagnostic categories: normal, lung cancer, pneumothorax, pneumonia, and interstitial lung disease (ILD). Comparative analyses demonstrated superior performance relative to established benchmark models, including EfficientNetB0, ResNet50, InceptionV3, DenseNet121, NASNetMobile, MobileNetV2, and Xception. The integrated ReciproCAM technique significantly enhanced clinical interpretability by highlighting the precise anatomical regions influencing the model’s diagnostic decisions. Ablation studies validated the optimal choice of the Adam optimizer and demonstrated the model’s computational feasibility, predicting and explaining 1000 images in approximately 150 seconds on a CPU-only device. This indicates strong potential for deployment in resource-constrained clinical settings.
- Open Access
- 6 May 2025
- Published by MDPI AG in Applied Sciences
- Vol. 15 (9) , 5138
RETRACTED: Choi, H.-S.; Yang, J. Innovative Use of Self-Attention-Based Ensemble Deep Learning for Suicide Risk Detection in Social Media Posts. Appl. Sci. 2024, 14, 893
The journal retracts the article titled “Innovative Use of Self-Attention-Based Ensemble Deep Learning for Suicide Risk Detection in Social Media Posts”
- 6 May 2025
- Published by MDPI AG in Applied Sciences
- Vol. 15 (9) , 5138
Open AccessRETRACTED: Choi, H.-S.; Yang, J. Innovative Use of Self-Attention-Based Ensemble Deep Learning for Suicide Risk Detection in Social Media Posts. Appl. Sci. 2024, 14, 893
The journal retracts the article titled “Innovative Use of Self-Attention-Based Ensemble Deep Learning for Suicide Risk Detection in Social Media Posts”
- Open Access
Energy-Efficient Dynamic Enhanced Inter-Cell Interference Coordination Scheme Based on Deep Reinforcement Learning in H-CRAN
The proliferation of 5G networks has revolutionized wireless communication by delivering enhanced speeds, ultra-low latency, and widespread connectivity. However, in heterogeneous cloud radio access networks (H-CRAN), efficiently managing inter-cell interference while ensuring energy conservation remains a critical challenge. This paper presents a novel energy-efficient, dynamic enhanced inter-cell interference coordination (eICIC) scheme based on deep reinforcement learning (DRL). Unlike conventional approaches that focus primarily on optimizing parameters such as almost blank subframe (ABS) ratios and bias offsets (BOs), our work introduces the transmission power during ABS subframes (TPA) and the channel quality indicator (CQI) threshold of victim user equipments (CTV) into the optimization process. Additionally, this approach uniquely integrates energy consumption into the scheme, addressing both performance and sustainability concerns. By modeling key factors such as signal-to-interference-plus-noise ratio (SINR) and service rates, we introduce the concept of energy-utility efficiency to balance energy savings with quality of service (QoS). Simulation results demonstrate that the proposed scheme achieves up to energy savings while enhancing QoS satisfaction, showcasing its potential to significantly improve the efficiency and sustainability of future 5G H-CRAN deployments.Open AccessEnergy-Efficient Dynamic Enhanced Inter-Cell Interference Coordination Scheme Based on Deep Reinforcement Learning in H-CRAN
The proliferation of 5G networks has revolutionized wireless communication by delivering enhanced speeds, ultra-low latency, and widespread connectivity. However, in heterogeneous cloud radio access networks (H-CRAN), efficiently managing inter-cell interference while ensuring energy conservation remains a critical challenge. This paper presents a novel energy-efficient, dynamic enhanced inter-cell interference coordination (eICIC) scheme based on deep reinforcement learning (DRL). Unlike conventional approaches that focus primarily on optimizing parameters such as almost blank subframe (ABS) ratios and bias offsets (BOs), our work introduces the transmission power during ABS subframes (TPA) and the channel quality indicator (CQI) threshold of victim user equipments (CTV) into the optimization process. Additionally, this approach uniquely integrates energy consumption into the scheme, addressing both performance and sustainability concerns. By modeling key factors such as signal-to-interference-plus-noise ratio (SINR) and service rates, we introduce the concept of energy-utility efficiency to balance energy savings with quality of service (QoS). Simulation results demonstrate that the proposed scheme achieves up to energy savings while enhancing QoS satisfaction, showcasing its potential to significantly improve the efficiency and sustainability of future 5G H-CRAN deployments. - Open Access
- 20 January 2024
- Published by MDPI AG in Applied Sciences
- Vol. 14 (2) , 893
RETRACTED: Innovative Use of Self-Attention-Based Ensemble Deep Learning for Suicide Risk Detection in Social Media Posts
Suicidal ideation constitutes a critical concern in mental health, adversely affecting individuals and society at large. The early detection of such ideation is vital for providing timely support to individuals and mitigating its societal impact. With social media serving as a platform for self-expression, it offers a rich source of data that can reveal early symptoms of mental health issues. This paper introduces an innovative ensemble learning method named LSTM-Attention-BiTCN, which fuses LSTM and BiTCN models with a self-attention mechanism to detect signs of suicidality in social media posts. Our LSTM-Attention-BiTCN model demonstrated superior performance in comparison to baseline models in the realm of classification and suicidal ideation detection, boasting an accuracy of 0.9405, a precision of 0.9385, a recall of 0.9424, and an F1-score of 0.9405. Our proposed model can aid healthcare professionals in recognizing suicidal tendencies among social media users accurately, thereby contributing to efforts to reduce suicide rates.
- 20 January 2024
- Published by MDPI AG in Applied Sciences
- Vol. 14 (2) , 893
Open AccessRETRACTED: Innovative Use of Self-Attention-Based Ensemble Deep Learning for Suicide Risk Detection in Social Media Posts
Suicidal ideation constitutes a critical concern in mental health, adversely affecting individuals and society at large. The early detection of such ideation is vital for providing timely support to individuals and mitigating its societal impact. With social media serving as a platform for self-expression, it offers a rich source of data that can reveal early symptoms of mental health issues. This paper introduces an innovative ensemble learning method named LSTM-Attention-BiTCN, which fuses LSTM and BiTCN models with a self-attention mechanism to detect signs of suicidality in social media posts. Our LSTM-Attention-BiTCN model demonstrated superior performance in comparison to baseline models in the realm of classification and suicidal ideation detection, boasting an accuracy of 0.9405, a precision of 0.9385, a recall of 0.9424, and an F1-score of 0.9405. Our proposed model can aid healthcare professionals in recognizing suicidal tendencies among social media users accurately, thereby contributing to efforts to reduce suicide rates.
- Open Access
- 31 December 2023
- Published by Digital Contents Society in Journal of Digital Contents Society
- Vol. 24 (12) , 3121-3130
Development of a Single-Person Care IoT service using AWS Greengrass and SageMaker
- 31 December 2023
- Published by Digital Contents Society in Journal of Digital Contents Society
- Vol. 24 (12) , 3121-3130
Open AccessDevelopment of a Single-Person Care IoT service using AWS Greengrass and SageMaker