Research Interests & Area of Expertise

  • Integer Optimization, Optimization under Uncertainty, Optimization Methods for Machine Learning/Artificial Intelligence

  • Applications of Optimization to Manufacturing, Logistics/Transportation, Energy, and Service Industries

Works in Progress

  1. Jongheon Lee, Kyungsik Lee, Single Unit Commitment under Uncertainty and its Application to Unit Decomposition Algorithms.

  2. Junyoung Kim, Kyungsik Lee, Lifting Heuristic of Probabilistic Cover Inequalities for the Chance-constrained Binary Knapsack Problem.

  3. Junyoung Kim, Kyungsik Lee, Strengthening Chvatal-Gomory Cuts for Knapack with Generalized Upper Bounds.

  4. Hakyong Kim, Junyoung Kim, Kyungsik Lee, Approximate Dynamic Programming Approach for Airport Gate Assignment Problem.

  5. Hojin Jung, Jongheon Lee, Kyungsik Lee, An Interval-based Two-stage Stochatic Optimization Model for the Unit Commitment Problem under Demand Uncertainty.

  6. Jinyeong Jeong, Seyoung Oh, Younsoo Lee, Kyungsik Lee, A Decomposition Approach for the Parallel Line Lot-sizing and Scheduling problem with Sequence-dependent Setup and Item Family.

  7. Junyoung Kim, Kyungsik Lee, On the Separation of Rank-1 Chvatal-Gomory Cuts for Knapsack with Generalized Upper Bounds.

  8. Junyoung Kim, Kyungsik Lee, Sparse Neural Networks with Threshold Activation : Expressivity & Complexity.

  9. Jongheon Lee, Seulgi Joung, Kyungsik Lee, Scalable optimization approaches for microgrid operation under stochastic islanding and net load.

  10. Suho Kang, Junyoung Kim, Seulgi Joung, Kyungsik Lee, Theoretical Analysis of Integer Programming Models for the Two-dimensional Two-staged Knapsack Problem, under review.

  11. Sungwon Hong, Younsoo Lee, Kyungsik Lee, Capacity Estimation for Semiconductor Wafer Fabrication Facilities via an Optimization Model based on Flexible Lead Times, under review.

  12. Jongyoon Park, Jinil Han, Kyungsik Lee, Integer Optimization Models and Algorithms for the Multi-period Non-sharable Resource Allocation Problem, under review.

  13. Jongheon Lee, Kyungsik Lee, Column-and-constraint Generation Approach to Partition-based Risk-averse Two-stage Stochastic Programs, under review

Publications in Refereed International Journals (or Conferences)

  1. 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 (on-line link, Manuscript), Oct. 2023.

  2. Seulgi Joung, Seyoung Oh, Kyungsik Lee, Comparative analysis of linear programming relaxations for the robust knapsack problem, Annals of Operations Research 323, 65-78 (on-line link, Manuscript), Apr. 2023.

  3. Junyoung Kim, Byungjoo Goo, Youngjoo Roh, Chungmok Lee, Kyungsik Lee, A Branch-and-Price Approach for Airport Gate Assignment Problem with Chance Constraints, Transportation Research Part B: Methodological 168, 1-26 (on-line link, Manuscript), Feb. 2023.

  4. Junhyeok Lee, Kyungsik Lee, Ilkyeong Moon, A reinforcement learning approach for multi-fleet aircraft recovery under airline disruption, Applied Soft Computing 129, 109556 (on-line link), Nov. 2022.

  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 (on-line link, Manuscript), Oct. 2022.

  6. Jisun Lee, Seulgi Joung, Kyungsik Lee, A Fully Polynomial Time Approximation Scheme for the Probability Maximizing Shortest Path Problem, European Journal of Operational Research 300(1), 35-45 (on-line link, Manuscript), Jul. 2022.

  7. (2022 Best Paper Award) Jongyoon Park, Jinil Han, Kyungsik Lee, Integer Optimization Model and Algorithm for the Stem Cell Cuturing Problem, Omega 108, 102566 (on-line link, Manuscript), Apr. 2022.

  8. Young-Soo Myung, Ilkyeong Moon, Jongheon Lee, Kyungsik Lee, Analyzing the effects of using both foldable and standard containers in ocean transportation, International Journal of Industrial Engineering: Theory, Applications and Practice 28(1) (on-line link), Oct. 2021.

  9. Sehwa Kim, Youngseon Jeong, Kyungsik Lee, Norm Ball Classifier for One-class Classification, Annals of Operations Research 303, 433-482(on-line link), Aug. 2021.

  10. Jongheon Lee, Si Young Lee, Kyungsik Lee, Multistage Stochastic Optimization for Microgrid Operation under Islanding Uncertainty, IEEE Transactions on Smart Grid 12(1), 56-66 (on-line link, Manuscript), Jan. 2021.

  11. Junyoung Kim, Kyungsik Lee, Measuring optimization performance of stochastic gradient descent via neural networks with threshold activation, Workshop on Optimization for Machine Learning (OPT2020) in Annual Conference on Neural Information Processing Systems (NeurIPS), December 2020.

  12. Younsoo Lee, Kyungsik Lee, Lot-sizing and Scheduling in Flat-Panel Display Manufacturing Process, Omega 93, 102036 (on-line link), Jun. 2020.

  13. Seulgi Joung, Kyungsik Lee, Robust optimization based heuristic algorithm for the chance-constrained knapsack problem using submodularity, Optimization Letters 14, 101-113 (on-line link), Feb. 2020.

  14. Dongwook Kim, Kyungsik Lee, Ilkyeong Moon, Stochastic facility location model for drones considering uncertain flight distance, Annals of Operations Research 283(1-2), 1283-1302 (on-line link), Dec. 2019.

  15. Sue-Jeong Kwon, Seulgi Joung, Kyungsik Lee, Comparative analysis of pattern-based models for the two-dimensional two-stage guillotine cutting stock problem, Computers and Operations Research 109, 159-169 (on-line link), Sep. 2019.

  16. Sungwon Hong, Jinyoung Choi, Jinil Han, Kyungsik Lee, Accelerated Dynamic Programming Algorithms for a Car Resequencing Problem in Automotive Paint Shops, Applied Mathematical Modeling 64, 285-297 (on-line link), 2018.

  17. Kyoungmi Hwang, Kyungsik Lee, Sungsoo Park, Variable selection methods for multi-class classification using a signomial function, Journal of the Operational Research Society 68(9), 1117-1130 (on-line link), 2017.

  18. Jinil Han, Jongyoon Park, Kyungsik Lee, Optimal Scheduling for Electric Vehicle Charging under Variable Maximum Charging Power, Energies 10(7), 933 (on-line link), 2017.

  19. Kyoungmi Hwang, Dohyun Kim, Kyungsik Lee, Chungmok Lee, Sungsoo Park, Embedded variable selection method using signomial classification, Annals of Operations Research 254(1), 89-109 (on-line link), 2017.

  20. Minchul Shin, Jeonghoon Mo, Kyungsik Lee, Cheol Lee, On the Interval Selection and Interpretation of the Probabilistic AHP for Uncertain Decision Making, International Journal of Industrial Engineering: Theory, Applications and Practice 24(1), 32-43 (on-line link), 2017.

  21. Kyungchul Park, Kyungsik Lee, Distribution-robust Loss-averse Optimization, Optimization Letters 11(1), 153-163 (on-line link), 2017.

  22. Hyunseok Cho, Kyoung-Kuk Kim, Kyungsik Lee, Computing Static-arbitrage Lower Bounds for Basket Options Prices, Optimization Letters 10(8), 1629-1644 (on-line link), 2016.

  23. Kyungchul Park, Kyungsik Lee, Distribution-robust single period inventory control problem with multiple unreliable suppliers, OR Spectrum 38(4), 949-966 (on-line link), 2016.

  24. Jinil Han, Kyungsik Lee, Chungmok Lee, Ki-Seok Choi, Sungsoo Park, Robust optimization approach for a chance-constrained binary knapsack problem, Mathematical Programming Ser.B 157(1), 277-296 (on-line link), 2016.

  25. Kyoungmi Hwang, Kyungsik Lee, Chungmok Lee, Sungsoo Park, Multi-class classification methods using a signomial function, Journal of the Operational Research Society 66, 434-449 2015.

  26. Cheol Lee, Jeonghoon Mo, Soeui Shin, Kyungsik Lee, The Grid Rotation Method and Its Application to the Glove Sizing System, Human Factors in Manufacturing and Service Industries 25(1), 58-65, 2015.

  27. Kyungsik Lee, Norman Kim, Myong K. Jeong, The Sparse Signomial Classification and Regression Model, Annals of Operations Research 216(1), 257-286, 2014.

  28. Jinil Han, Kyungsik Lee, Chungmok Lee, Sungsoo Park, Exact algorithms for a bandwidth packing problem with queueing delay guarantees, INFORMS Journal on Computing 25(3), 585-596, 2013.

  29. Chungmok Lee, Kyungsik Lee, Sungsoo Park, Benders decomposition approach for the robust network design problems under demand uncertainty, Networks 62(1), 1-16, 2013.

  30. Chungmok Lee, Kyungsik Lee, Kyungchul Park, Sungsoo Park, Branch-and-Price-and-Cut approach for the robust network design problems without flow bifurcations under demand uncertainty, Operations Research 60(3), 604-610, 2012.

  31. Chungmok Lee, Kyungsik Lee, Sungsoo Park, Robust Vehicle Routing Problem with Deadlines and Travel Time/Demand Uncertainty, Journal of the Operational Research Society 63, 1204-1306, 2012.

  32. Kyungsik Lee, Integral polyhedra related to integer multicommodity flows on a cycle, Discrete Applied Mathematics 158, 235-238, 2010.

  33. Kyungsik Lee, Kyungchul Park, Sungsoo Park, A compact formulation for the ring loading problem with integer demand splitting, Operations Research Letters 37, 111-113, 2009.

  34. Kyungchul Park, Kyungsik Lee, Sungsoo Park, An LP-based Approach to the Ring Loading Problem with Integer Demand Splitting, Journal of Operations Research Society of Japan 52, 35-45, 2009.

  35. Sung-Pil Hong, Kyung Min Kim, Kyungsik Lee, Bum Hwan Park, A pragmatic algorithm for the train-set routing: The case of Korea high-speed railway, Omega 37, 637-645, 2009.

  36. Ojeong Kwon, Kyungsik Lee, Donghan Kang, Sungsoo Park, A Branch-and-Price Algorithm for a Targeting Problem, Naval Research Logistics 54, 732-741, 2007.

  37. Wanmo Kang, Kyungsik Lee, Optimization Problems in the Simulation of Multifactor Portfolio Credit Risk, Lecture Notes in Computer Science 3982, 777-784, 2006.

  38. Dong-Seok Sun, Tae-Eog Lee, Kyungsik Lee, A Column Generation Approach for Pickup Cycle Formation in Multi-Head Gantry-Type Component Mounting Machine, International Journal of Industrial Engineering: Theory, Applications and Practice 10(4), 569-576, 2003.

  39. Kyungsik Lee, Kug Chang Kang, Taehan Lee, and Sungsoo Park, An Optimization Approach to Routing and Wavelength Assignment in WDM All-optical Networks without Wavelength Conversion, ETRI Journal 24(2), 131-141, April 2002.

  40. Gue-Woong Jeong, Kyungsik Lee, Sungsoo Park, and Kyungchul Park, A Branch-and-price Algorithm for the Steiner Tree Packing Problem, Computers & Operations Research 29, 221-241, March 2002.

  41. Taehan Lee, Kyungsik Lee, Sungsoo Park, Optimal Routing and Wavelength Assignment in WDM Ring Networks, IEEE Journal on Selected Areas in Communication 18, 2146-2154, 2000.

  42. Kyungsik Lee, Sungsoo Park, Kyung-Il Choe, and Cheehang Park, Routing and Wavelength Assignment in WDM All-optical Networks, Electronics Letters 36, 964-966, 2000.

  43. Donghan Kang, Kyungsik Lee, Kyungchul Park, Sungsoo Park, and Sang-Baeg Kim, Design of Local Networks using USHRs, Telecommhnication Systems 14, 197-217, 2000.

  44. Kyungchul Park, Kyungsik Lee, Sungsoo Park, and Heesang Lee, Telecommunication Node Clustering with Node Compatibility and Network Survivability Requirements, Management Science 46, 363-374, 2000.

  45. Ojeong Kwon, Donghan Kang, Kyungsik Lee, and Sungsoo Park, Lagrangian Relaxation Approach to the Targeting Problem, Naval Research Logistics 46, 640-653, 1999.

  46. Kyungsik Lee, Kyungchul Park, Sungsoo Park, and Heesang Lee, Economic Spare Capacity Assignment for DCS-mesh Restorable Networks, European Journal of Operational Research 110, 63-75, 1998.

  47. Ojeong Kwon, Kyungsik Lee, and Sungsoo Park, Targeting and Scheduling Problem for Field Artillery, Computers & Industrial Engineering 33, 693-696, 1997.

  48. Kyungchul Park, Kyungsik Lee, and Sungsoo Park, An Extended Formulation Approach to the Edge-weighted Maximal Clique Problem, European Journal of Operational Research 95, 671-682, 1996.

  49. Kyungsik Lee, Kyungchul Park, and Sungsoo Park, Design of Capacitated Networks with Tree Configurations, Telecommunication Systems 6, 1-19, 1996.

  50. Kyungchul Park, Kyungsik Lee, Sungsoo Park, and Sunghwan Kim, Modeling and Solving the Spatial Block Scheduling Problem arising in a Shipbuilding Company, Computers & Industrial Engineering 30, 357-364, 1996.

Publications in Refereed Journals (Regional)

  1. Jongheon Lee, Kyungsik Lee, A Unit Decomposition Approach for the Stochastic Unit Commitment Problem under Demand Uncertainty, Journal of the Korean Institute of Industrial Engineers 49(4), 284-293, August 2023.

  2. Seyoung Oh, Jongyoon Park, Kyungsik Lee, Multi-Agent Route Optimization for Robotic Mobile Fulfillment Systems, Journal of the Korean Institute of Industrial Engineers 46(3), 230-244, June 2020.

  3. Jiyoung Choi, Sangrak Lee, Kyungsik Lee, Jeong-hun Lee, Development of a Decision Support System for Estimation of Transportation Cost of 3LP Provider, Korean Management Science Review 34(1), 1-13, 2017.

  4. Kyungchul Park, Kyungsik Lee, Optimality of the Sole Sourcing under Random Yield, Journal of the Korean Institute of Industrial Engineers 41(3), 324-329, 2015.

  5. Kyungsik Lee, Separation Heuristic for the Rank-1 Chvatal-Gomory Inequalities for the Binary Knapsack Problem, Journal of the Korean Institute of Industrial Engineers 38(2), 2012.

  6. Kyungchul Park and Kyungsik Lee, On the Separation of the Rank-1 Chvatal-Gomory Inequalities for the Fixed-Charge 0-1 Knapsack Problem, Journal of Korean ORMS Society 36, 43-50, 2011.

  7. Kyungsik Lee, Signomial classification method with L0-regularization, IE Interfaces 24(1), 151-155, 2011.

  8. Young-Seon Jeong, Chungmok Lee, Norman Kim, Kyungsik Lee, Remote health monitoring of Parkinson's disease severity using signomial regression model, IE Interfaces 23(4), 1-7, 2010.

  9. Kyungchul Park and Kyungsik Lee, A generalization of the robust inventory problem with non-stationary cost, International Journal of Management Science 16(3), 95-102, 2010.

  10. Kyungsik Lee, On the Convex Hull of Multicuts on a Cycle, International Journal of Management Science 15(2), 119-123, 2009.

  11. Sang Hwa Song, Kyungsik Lee, A Mixed Integer Linear Programming Approach for the Profit Based Unit Commitment Problem under Non-Linear Fuel Consumption Constraint and Maintenance Cost(in Korean), Korean Management Science Review 25(1), 43-54, 2008.

  12. Kyungsik Lee, Younghyo Song, An Algorithm and a Prototype System for the Shift Planning in Postal Logistics Networks(in Korean), Korean Journal of Logistics 15(2), 5-24, 2007.

  13. Kyungchul Park, Kyungsik Lee, A Note on Robust Combinatorial Optimization Problem, International Journal of Management Science 13(1), 115-119, 2007.

  14. Kyungsik Lee, Sang Hwa Song, An Explicit Column Generation Algorithm for the Profit Based Unit Commitment Problem in Electric Power Industry(in Korean), IE Interfaces 20(2), 186-194, 2007.

  15. Kyungsik Lee, Taehan Lee, Sungsoo Park, An Integer Programming Approach to Packing Lightpaths on WDM Networks(in Korean), Journal of the Korean Institute of Industrial Engineers 32(3), 219-225, 2006.

  16. Taehan Lee, Kyungsik Lee, Sungsoo Park, Routing and Wavelength Assignment in Survivable WDM Networks without Wavelength Conversion, International Journal of Management Science 11(2), 85-103, 2005.

  17. Heejeong Jang, Kyungsik Lee, Eunjeong Choi, Sungsoo Park, A Tabu Search Algorithm for the Vehicle Routing Problem with Time Window and Dock Capacity Constraints(in Korean), Journal of Korean ORMS Society 30, 45-60, 2005.

  18. Deokseong Kim, Sungsoo Park, Kyungsik Lee, Kyungchul Park, A Branch-and-Price Approach to the ATM Switching Node Location Problem, Industrial Engineering & Management Systems 3(2), 92-99, 2004.

  19. Kyungsik Lee, A Cutting-Plane Generation Method for a Variable Capacity (0,1)-Knapsack Problem with General Integer Variables, International Journal of Management Science 10(1), 97-106, 2004.

  20. Jongik Byun, Kyungsik Lee, Sungsoo Park, Sungyeol Kang, An Integer Programming Approach to the Subway Daily Crew Scheduling Problem (in Korean), Journal of Korean ORMS Society 27, 67-86, Dec 2002.

  21. Soung Ryong Yee, Ji Ung Sun, and Kyungsik Lee, A Study on a To-Be System Design for the Operational Information System of Postal Service (in Korean),Journal of the Korean Institute of Industrial Engineers 28, 302-318, 2002.

  22. Gue-Woong Jeong, Kyungsik Lee, Sungsoo Park, and Kyungchul Park, Column Generation Approach to the Steiner Tree Packing Problem (in Korean), Journal of Korean ORMS Society 25, 17-33, 2000.

  23. Kyungsik Lee and Sungsoo Park, Cutting Planes for the (0,1)-Knapsack Problems with Variable Capacity (in Korean), Journal of Korean ORMS Society 25, 1-15, 2000.

  24. Kyungsik Lee, Ojeong Kwon, Sungsoo Park, and Kyungchul Park, Complexity of the Fire Sequencing Problem, International Journal of Management Science 5, 55-59, 1999.

  25. Deokseong Kim, Kyungsik Lee, Sungsoo Park, and Kyungchul Park, Algorithm for the ATM Switching Node Location Problem (in Korean), Journal of Korean ORMS Society 24, 93-107, 1999.

  26. Kyungsik Lee, Sungsoo Park, and Kyungchul Park, Polyhedral Cutting Planes for the Bipartite Precedence-Constrained Knapsack Problems (in Korean), Journal of Korean ORMS Society 23, 1-10, 1998.