A note on treating a second order cone program as a special case of a semidefinite program. - Chee-Khian Sim; Gongyun Zhao (Math. Program., 2005)

A note on the Lipschitz continuity of the gradient of the squared norm of the matrix-valued Fischer-Burmeister function. - Chee-Khian Sim; Jie Sun 001; Daniel Ralph (Math. Program., 2006)

Underlying paths in interior point methods for the monotone semidefinite linear complementarity problem. - Chee-Khian Sim; Gongyun Zhao (Math. Program., 2007)

Remote Sensing of Aerosols over Penang Island from Satellite Measurements. - Chee-Khian Sim; Hwee San Lim; Chow-Jeng Wong; M. Z. MatJafri; Khiruddin Abdullah (CGIV, 2008)

Asymptotic Behavior of Underlying NT Paths in Interior Point Methods for Monotone Semidefinite Linear Complementarity Problems. - Chee-Khian Sim (J. Optim. Theory Appl., 2011)

Superlinear Convergence of an Infeasible Predictor-Corrector Path-Following Interior Point Algorithm for a Semidefinite Linear Complementarity Problem Using the Helmberg–Kojima–Monteiro Direction. - Chee-Khian Sim (SIAM J. Optim., 2011)

Optimal policies for inventory systems with two types of product sharing common hardware platforms: Single period and finite horizon. - Mabel C. Chou; Chee-Khian Sim; Xue-Ming Yuan (Eur. J. Oper. Res., 2013)

The impact of supply chain visibility when lead time is random. - Ek Peng Chew; Loo Hay Lee; Chee-Khian Sim (OR Spectr., 2013)

Inexact subgradient methods for quasi-convex optimization problems. - Yaohua Hu; Xiaoqi Yang 001; Chee-Khian Sim (Eur. J. Oper. Res., 2015)

On finding a generalized lowest rank solution to a linear semi-definite feasibility problem. - Chee-Khian Sim (Oper. Res. Lett., 2015)

Infinite horizon optimal policy for an inventory system with two types of product sharing common hardware platforms. - Mabel C. Chou; Chee-Khian Sim; Xue-Ming Yuan (Oper. Res. Lett., 2017)

Complexity of the relaxed Peaceman-Rachford splitting method for the sum of two maximal strongly monotone operators. - Renato D. C. Monteiro; Chee-Khian Sim (Comput. Optim. Appl., 2018)

Profit Sharing Agreements in Decentralized Supply Chains: A Distributionally Robust Approach. - Qi Fu; Chee-Khian Sim; Chung-Piaw Teo (Oper. Res., 2018)

Interior point method on semi-definite linear complementarity problems using the Nesterov-Todd (NT) search direction: polynomial complexity and local convergence. - Chee-Khian Sim (Comput. Optim. Appl., 2019)

Policies for inventory models with product returns forecast from past demands and past sales. - Mabel C. Chou; Chee-Khian Sim; Xue-Ming Yuan (Ann. Oper. Res., 2020)

A FISTA-type accelerated gradient algorithm for solving smooth nonconvex composite optimization problems. - Jiaming Liang; Renato D. C. Monteiro; Chee-Khian Sim (Comput. Optim. Appl., 2021)

Convergence Rates for the Relaxed Peaceman-Rachford Splitting Method on a Monotone Inclusion Problem. - Chee-Khian Sim (J. Optim. Theory Appl., 2023)

Refining asymptotic complexity bounds for nonconvex optimization methods, including why steepest descent is o(ε-2) rather than 𝒪(ε-2). - Serge Gratton; Chee-Khian Sim; Philippe L. Toint (CoRR, 2024)

Reduction from the partition problem: Dynamic lot sizing problem with polynomial complexity. - Chee-Khian Sim (CoRR, 2024)

Superlinear convergence of an interior point algorithm on linear semi-definite feasibility problems. - Chee-Khian Sim (Optim. Methods Softw., 2025)