SPS Lab @ SSU We Optimize!

Research Interests

Works in Progress

  1. A Branch-and-Price Algorithm for the Parallel-line Lot-sizing and Scheduling Problem in Flat-panel Display Manufacturing Process, under review.
  2. A Robust Optimization Approach for E-bus Charging and Discharging Scheduling with Vehicle-to-Grid Integration, under review.
  3. Two-stage Robust Optimization Approach for Integrated Supply Chain with Hybrid-dark Stores, under review.
  4. An Approximate Dynamic Programming Approach to Wafer-lot Scheduling for Parallel Multi-chamber Equipment in Semiconductor Fabrication Lines, under review.

Publications (International)

  1. 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, Mar. 2025. (on-line link)
  2. 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)
  3. 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)
  4. 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, May. 2025. (In press)

International Conferences

  1. 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.
  2. 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.
  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 IFORS 2021, Seoul (virtual), South Korea, Aug. 2021.
  4. 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)