Research Interests

• 경영과학 방법론을 적용하여 생산, 물류, 에너지, 서비스 등 다양한 산업에서 발생하는 문제를 해결하는 일체의 과정
  • 스마트 생산시스템(Smart Production Systems) 구축, 생산계획 수립 및 스케줄링
  • 전기자동차 충전소의 설계 및 운영 최적화
  • 자동화된 물류 창고 (Robotic Mobile Fulfillment Systems)의 운영 최적화
• 경영과학 및 최적화 이론 및 해법
  • Theory: Polyhedral Analysis, Valid Inequalities, Extended Formulation
  • Algorithm: Cutting plane, Branch-and-Cut, Branch-and-Price, Benders Decomposition
• 불확실성 하에서의 순차적 의사결정 기법
  • Approximate Dynamic Programming
  • Stochastic Programming & Robust Optimization
  • Reinforcement Learning

Works in Progress

1. Two-stage Robust Optimization Approach for Integrated Supply Chain with Hybrid-dark Stores, under review.
2. An Approximate Dynamic Programming Approach to Wafer-lot Scheduling for Parallel Multi-chamber Equipment in Semiconductor Fabrication Lines, under review.
3. Self-Adaptive Prompt Engineering for Cost-Efficient Language Models: Switching between Chain-of-Thought and Direct Answer, under review.
4. Structure-Preserving Process Case Embeddings via Directed Graph Convolutional Networks, under review.
5. A Robust Optimization Approach for the Multi-period Strip Cutting Problem with Multi-cutter Slitting Machines.
6. Stochastic Programming Approach to Supply Chain Model with Third-Party Return Management System.

Publications (International)

1. Seyoung Oh, Jinyeong Jeong, Younsoo Lee^*, Kyungsik Lee^*, A Branch-and-Price Algorithm for the Parallel-line Lot-sizing and Scheduling Problem in Flat-panel Display Manufacturing Process, Omega, 138, 103386, Jan. 2026. (on-line link)
2. Mingyu Kang, Bosung Lee, Younsoo Lee^*, A Robust Optimization Approach for E-bus Charging and Discharging Scheduling with Vehicle-to-Grid Integration, Mathematics 13(9), 1380, May. 2025. (on-line link)
3. Sungwon Hong, Younsoo Lee^*, Kyungsik Lee^*, Capacity Estimation for Semiconductor Wafer Fabrication Facilities via an Optimization Model based on Flexible Lead Times, IEEE Transactions on Semicnductor Manufacturing 38(2), 292-310, May. 2025. (on-line link)
4. Younsoo Lee, Kyungsik Lee^*, Valid Inequalities and Extended Formulations for Lot-sizing and Scheduling Problem with Sequence-dependent Setups, European Journal of Operational Research 310(1), 201-216, Oct. 2023. (on-line link)
5. Younsoo Lee, Kyungsik Lee^*, New Integer Optimization Models and an Approximate Dynamic Programming Algorithm for the Lot-sizing and Scheduling Problem with Sequence-dependent Setups, European Journal of Operational Research 302(1), 230-243, Oct. 2022. (on-line link)
6. Younsoo Lee, Kyungsik Lee^*, Lot-sizing and Scheduling in Flat-Panel Display Manufacturing Process, Omega 93, 102036, Jun. 2020. (on-line link)

Publications (Domestic)

1. Mingyu Kang, Donguk Min, Bosung Lee, Younsoo Lee^*, Optimization of Electric Bus Charging and Discharging Schedules with Vehicle-to-Grid Technology, The Transactions of the Korean Institute of Electrical Engineers 74(5), 761-774, May. 2025.

International Conferences

1. Sungwon Hong, Younsoo Lee, Kyungsik Lee, “An Optimization Model and Approximate Dynamic Programming Algorithms for a Wafer-Lot Scheduling Problem in Parallel Multi-Chamber Equipment” in EURO 2025, Leeds, UK, June 2025.
2. Younsoo Lee, Kyungsik Lee, “Valid Inequalities and Extended Formulations for Single-period Relaxation of Lot-sizing and Scheduling Problem” in EURO 2022, Espoo, Finland, Jul. 2022.
3. Sungwon Hong, Younsoo Lee, Kyungsik Lee, “An Optimization Model based on Flexible Lead Times for Semiconductor Wafer Fabrication” in EURO 2022, Espoo, Finland, Jul. 2022.
4. Younsoo Lee, Kyungsik Lee, “New Integer Optimization Models and Approximate Dynamic Programming Algorithm for the Lot-sizing and Scheduling Problem with Sequence-dependent Setups” in IFORS 2021, Seoul (virtual), South Korea, Aug. 2021.
5. Younsoo Lee, Kyungsik Lee, “On the Discrete Lot-sizing and Scheduling Problem with Sequence-dependent Setup” in ISMP 2018, Bordeaux, France, Jul. 2018.

Domestic Conferences

1. Sungwon Hong, Younsoo Lee, Kyungsik Lee, “An Optimization Model based on Flexible Lead Times for Semiconductor Wafer Fabrication” in KIIE 2022, Jeju, South Korea, Jun. 2022.
2. Jinyeong Jeong, Younsoo Lee, Kyungsik Lee, “A Decomposition Approach for the Parallel Line Lot-sizing and Scheduling Problem with Sequence-dependent Setup and Item Family” in KIIE 2021, Seoul, South Korea, Nov. 2021.
3. Younsoo Lee, Kyungsik Lee, “New Integer Optimization Models and Approximate Dynamic Programming Algorithm for the Lot-sizing and Scheduling Problem with Sequence-dependent Setups” in KIIE 2020, Seoul, South Korea, Nov. 2020.
4. Younsoo Lee, Kyungsik Lee, “An Extended Formulation Approach for the Lot-sizing and Scheduling Problem with Sequence-dependent Setups and Production Run Limit” in KIIE 2018, Seoul, South Korea, Nov. 2018.
5. Younsoo Lee, Kyungsik Lee, “On the Discrete Lot-sizing and Scheduling Problem with Sequence-dependent Setup” in KORMS 2017, Seoul, South Korea, Nov. 2017.

Research Projects (@ SSU)

• 순환 경제를 위한 다중-계층 폐쇄형 공급망 기반 스마트 반품 관리 시스템 개발
  • Co-PI, 정석물류학술재단 학술연구지원사업 (2025.01 - 2025.12)
• 스마트 충전 기술 도입에 따른 전기차 충전소 운영 최적화 기법
  • PI, 숭실대학교 (2023.05 - 2024.04)