Research

Working Papers

• • Linear programming based heuristic algorithms for tunnel assignment and reconfiguration in MPLS networks

  • Theoretical analysis of integer programming models for the two-dimensional two-staged knapsack problem

  • Using submodularity in solving the robust bandwidth packing problem with queuing delay guarantees 

  • Scalable optimization approaches for microgrid operation under stochastic islanding and net load

  • Branch-and-cut algorithm for multiband robust discrete optimization problems

Published Papers - International Journal (Google scholar) 

• S. Joung*. "A new sequential lifting of robust cover inequalities." Optimization Letters 2023:1-17. https://doi.org/10.1007/s11590-023-02027-3 

• S. Joung, S. Oh* and K. Lee*. "Comparative analysis of linear programming relaxations for the robust knapsack problem." Annals of Operations Research 323(1) 2023: 65-78. https://doi.org/10.1007/s10479-022-05161-w

• K. Seo, S. Joung, C. Lee and S. Park*. "A closest Benders cut selection scheme for accelerating the Benders decomposition algorithm." INFORMS Journal on Computing 34(5) 2022: 2804-2827. https://doi.org/10.1287/ijoc.2022.1207 

• J. Lee, S. Joung* and K. Lee*. "A fully polynomial time approximation scheme for the probability maximizing shortest path problem." European Journal of Operational Research 300(1) 2022: 35-45. https://doi.org/10.1016/j.ejor.2021.10.018

• S. Joung and S. Park*. "Robust mixed 0-1 programming and submodularity." INFORMS Journal on Optimization 3(2) 2021: 183-199. https://doi.org/10.1287/ijoo.2019.0042

• S. Joung and K. Lee*. "Robust optimization-based heuristic algorithm for the chance-constrained knapsack problem using submodularity." Optimization Letters 14(1) 2020: 101-113. https://doi.org/10.1007/s11590-019-01445-6 

• S. Joung, J. Lim, C. Lee*, J. Shin, I. Jung and S. Park*. "A linear programming based heuristic algorithm for bandwidth packing problem with scheduling." Journal of the Operational Research Society 71(2) 2020: 250-263. https://doi.org/10.1080/01605682.2018.1542959 

• SJ. Kwon, S. Joung and K.Lee*. "Comparative analysis of pattern-based models for the two-dimensional two-stage guillotine cutting stock problem." Computers & Operations Research 109 2019: 159-169. https://doi.org/10.1016/j.cor.2019.05.005

• S. Joung and S. Park*. "Lifting and separation of robust cover inequalities." Networks 72(2) 2018: 272-305. https://doi.org/10.1002/net.21829

• S. Joung and S. Park*. "Lifting of probabilistic cover inequalities." Operations Research Letters 45(5) 2017: 513-518. https://doi.org/10.1016/j.orl.2017.08.006

*: corresponding authors

Published Papers - Domestic Journal

• 이현태, 윤범, 조예림, 이수현, 정슬기*, "정수계획법을 활용한 시차를 고려한 온라인 학회 스케줄링 방법 제안." 경영과학 40(1) 2023: 61-70. https://doi.org/10.7737/KMSR.2023.40.1.061

• 전홍배, 신기태, 정슬기*, "정량 분석을 통해 살펴본 산업공학 전공의 현황." 대한산업공학회지 48(3) 2022: 265-270. https://doi.org/10.7232/JKIIE.2022.48.3.265
  (대한산업공학회 산업공학 위상강화 TF팀, 2021-2022)

• 정슬기*, "k-부분보형 부등식과 불확실성을 고려한 이산최적화 문제." 한국경영과학회지 47(2) 2022: 25-34. https://doi.org/10.7737/JKORMS.2022.47.2.025
  (전남대학교 교내 과제 2021-2158)

Research Projects

• 한국전력기술, January 2023 - December 2023

  • "불확실성 기반 해상풍력단지 정비계획 모델링 및 최적화 기술자문"

• National Research Foundation of Korea, March 2021 - February 2024

  • "Decision making under uncertainty and k-submodularity", PI

• National Research Foundation of Korea, May 2021 - February 2027

  • 인공지능 혁신공유대학 사업단, 전남대학교 산업공학과 참여교수

  • "문제해결과 알고리즘" 공유교과목 운영

  • "AI 알고리즘" 공동운영교과목 개선

• SK Telecom, July 2017 - February 2018

  • with Broadband Tech. Lab, Network Technology R&D center, SK Telecom, Republic of Korea

  • "Traffic optimization and scheduling algorithms for L3 level transport networks"

• SK Telecom, October 2016 - April 2017

  • with Broadband Tech. Lab, Network Technology R&D center, SK Telecom, Republic of Korea

  • "Bandwidth calendaring algorithms in the design of path computing environment (PCE) for L2 level transport networks"

• National Research Foundation of Korea, June 2016 - May 2019

  • "Studies on the polyhedral structures of the solution sets of robust optimization problems"

• SK Innovation, Ph.D. Intern, June 2014 - August 2014

  • in Optimization and Analysis Lab

  • "Vessel arrival scheduling considering uncertainty"

Conference Presentations

• S. Joung. "Branch-and-cut for the multiband robust optimization problems." Conference of the Korean Institute of Industrial Engineers. in Jeju, Republic of Korea. May 2023.

• S. Joung. "A lifting algorithm for robust cover inequalities." Conference of Korean Operations Research and Management Science Society. in Jeju, Republic of Korea. June 2022.

• S. Joung, J. Lee and K. Lee. "An improved approximation scheme for the stochastic shortest path problem." Conference of the Korean Institute of Industrial Engineers. in Seoul, Republic of Korea. November 2021.

• S. Joung and K. Lee. "A heuristic algorithm for the chance-constrained knapsack problem using submodularity." EURO 2019. in Dublin, Ireland. June 2019. 

• J. Lee, S. Joung and K.Lee, "An approximation algorithm for a probability maximization knapsack problem.", EURO 2019. in Dublin, Ireland. June 2019.

• J. Lee, S. Joung and K.Lee, "An approximation scheme for a probability maximizing combinatorial optimization problem.", Conference of the Korean Institute of Industrial Engineers. in Gwangju, Republic of Korea. April 2019.

• J. Lim, S. Joung, C. Lee, J. Shin, I. Jung and S. Park, "A heuristic algorithm for bandwidth packing problem with flow scheduling for inter-data centers.", Conference of Korean Operations Research and Management Science Society. in Seoul, Republic of Korea. October 2018.

• S. Joung and S. Park. "Robust MIP problems and submodular inequalities." Conference of the Korean Institute of Industrial Engineers. in Gyeongju, Republic of Korea. April 2018.

• S. Joung and S. Park. "Cardinality constrained robust MIP and submodular polyhedron." 2017 INFORMS Annual Meeting. in Houston, Texas, U.S.A. October 2017.

• S. Joung and S. Park. "A lifting algorithm for probabilistic cover inequalities." Conference of the Korean Institute of Industrial Engineers. in Jeju, Republic of Korea. April 2016.

• S. Joung and S. Park. "Lifting and separation of robust cover inequalities." Conference of the Korean Institute of Industrial Engineers. in Jeju, Republic of Korea. April 2015.