Research Publications | Hiroshi Okajima | Control Engineering

Japanese articles link [日本語]

Journal Articles: 

[31] Hiroshi Okajima and Kakeru Ono, Cyclic Reformulation-Based Identification and Polytopic Uncertainty Modeling for Multirate Systems, IEEE ACCESS, submitted [2607.09194] arxiv 

[30] Hiroshi Okajima, Closed-Loop Identification of Periodically Time-Varying Systems via Cyclic Reformulation, Automatica, submitted [2605.29385] arxiv

[29] Rentaro Iwai, Natsuki Hikasa and Hiroshi Okajima, Robust Path Following Control for Vehicles with Uncertain Steering Resistance Using Model Error Compensation, IEEE Access, submitted [2604.19248] arxiv

[28] Hiroshi Okajima, Stable Inversion of Discrete-Time Linear Periodically Time-Varying Systems via Cyclic Reformulation, Automatica, submitted [2603.23147] arxiv 

[27] Hiroshi Okajima, Shun Shirahama, Tatsunori Hayashi, Nobutomo Matsunaga, From Noise to Knowledge: System Identification with Systematic Polytope Construction via Cyclic Reformulation, IEEE Access, Volume 14, pp. 76185-76199 (2026) [2601.12695] arxiv

[26] Hiroshi Okajima, LMI Optimization Based Multirate Steady-State Kalman Filter Design, IEEE Access, Volume 14, pp. 50679-50690 (2026) (Open Access), [2602.01537]arxiv , GitHub(Python, MATLAB)

[25] Hiroshi Okajima, Risa Furukawa and Nobutomo Matsunaga, System Identification Under Multi-rate Sensing Environment, Journal of Robotics and Mechatronics, Vol. 37, No. 5, pp. 1102-1112  (2025) (Open Access)  [2503.12750]arxiv [Detail]

[24] Hiroshi Okajima, Yusuke Fujimoto, Hiroshi Oku and Haruto Kondo, Cyclic Reformulation-Based System Identification for Periodically Time-Varying Systems, IEEE ACCESS, Vol. 13, pp. 26483-26493  (2025) (Open Access) [Detail]

[23] Hiroshi Okajima, Kenta Arinaga and Atsuo Hayashida, Design of observer-based feedback controller for multi-rate systems with various sampling periods using cyclic reformulation, IEEE ACCESS, Vol. 11, pp. 121956-121965 (2023) (Open Access) MATLAB code [Detail]

[22] Nobutomo Matsunaga, Kazuhi Murata and Hiroshi Okajima, Robust cooperative transport system with Model Error Compensator using multi-robots which has suction-cups, Journal of Robotics and Mechatronics, Vol. 35, No. 6, pp. 1583-1592 (2023) (Open Access)

[21] Nobutomo Matsunaga, Ikuo Yamamoto, Hiroshi Okajima, Navigation System for Personal Mobility Vehicles Following a Cluster of Pedestrians in a Corridor Using Median of Candidate Vectors Observer, Journal of Robotics and Mechatronics, Vol. 35, No. 6, pp. 1562-1572 (2023) 

[20] Hiroshi Okajima, Yohei Hosoe and Tomomichi Hagiwara, State Observer under Multi-rate Sensing Environment and Its Design using l2 -Induced Norm, IEEE ACCESS (2023), Vol. 11,  pp. 20079 - 20087 [Detail] MATLAB File Exchange - MATLAB Central 

[19] Nobutomo Matsunaga, Masaki Kuwahara, Hiroshi Okajima and Gou Koutaki, Analysis of Measuring Precision of 3D Model of Ishigaki Stone in Kumamoto Castle Using Automatic CMG Crane System, JRM, Vol.34 No.3 pp. 622-630 doi: 10.20965/jrm.2022.p0622 (2022) 

[18] Ryuichiro Yoshida, Hiroshi Okajima and Takumi Sato, Model error compensator design for continuous- and discrete-time non-minimum phase systems with polytopic-type uncertainties, SICE Journal of Control, Measurement, and System Integration, Volume 15 Issue 2 pages 141-153 (2022) (T&F, Open Access) MECpage [Detail]

[17] Hiroshi Okajima, Yasuaki Kaneda and Nobutomo Matsunaga, State estimation method using median of multiple candidates for observation signals including outliers, SICE Journal of Control, Measurement, and System Integration, Volume 14 Issue 1 pages 257-267 (2021) (T&F, Open Access) SupportPage [Detail] Outlier-Robust State Estimator :JCMSI 2021 - File Exchange - MATLAB Central 

[16] R. Yoshida, Y. Tanigawa, H. Okajima, and N. Matsunaga, A Design Method of Model Error Compensator for Systems with Polytopic-type Uncertainty and Disturbances, SICE Journal of Control, Measurement, and System Integration, Volume 14 Issue 2 Pages 119-127 (2021) (T&F, Open Access) MECpage [Detail]

[15] H. Okajima, K. Fujinami, Estimation of Robust Invariant Set for Switched Linear Systems using Recursive State Updating and Robust Invariant Ellipsoid, SICE Journal of Control, Measurement, and System Integration, Volume 14 Issue 1 Pages 97-106 (2021) (T&F, Open Access) YouTube, SupportPage [Detail]

[14] H. Okajima, Y. Nakabayashi and N. Matsunaga, Signal-Limitation Filters to Simultaneously Satisfy Constraints of Velocity and Acceleration Signals, SICE Journal of Control, Measurement, and System Integration, Volume 13 Issue 1 Pages 1-8 (2020) (T&F, Open Access) MECpage

[13] H. Okajima, Y. Minami and N. Matsunaga：A Control Structure for Unilateral System with Communication Rate Constraint, SICE Journal of Control, Measurement, and System Integration, Vol. 11, No. 6, pp. 510-516（2018） (T&F, Open Access) QUANTIZERpage

[12] G. Ichimasa, H. Okajima, K. Okumura and N. Matsunaga：Model Error Compensator with Parallel Feed-Forward Filter, SICE Journal of Control, Measurement, and System Integration, Vol.10, No.5, pp.468-475 (2017)  (T&F, Open Access) MECpage [Detail]

[11] H. Okajima, K. Sawada and N. Matsunaga：Dynamic Quantizer Design Under Communication Rate Constraints, IEEE Transactions on Automatic Control, Vol.61, No.10, pp.3190-3196 (2016) SupportPage [Detail]

[10] G. Koutaki, H. Okajima, N. Matsunaga and K. Uchimura：Color quantization and optimization of luminance for digital mirror device–based projector, IEEE transactions on Consumer Electronics, Vol.62, No.2, pp.103-110 (2016) QUANTIZERpage

[9] H. Okajima and T. Asai：Tracking Performance Limitation for 1-DOF Control Systems Using a Set of Attainable Outputs, SICE Journal of Control, Measurement, and System Integration Vol.8, No.5, pp.348-353 (2015) (T&F, Open Access) [Detail]

[8] H. Okajima, M. Honda, R. Yoshino and N. Matsunaga：A Design Method of Delta-Sigma Data Conversion System with Pre-Filter, SICE Journal of Control, Measurement, and System Integration Vol.8, No.2, pp.154-160 (2015)  (T&F, Open Access) QUANTIZERpage [Detail]

[7] A. T. Zengin, Y. Maruno, H. Okajima, N. Matsunaga：Maneuverability Improvement of Front-Drive-Type Electric Wheelchair STAVi, SICE Journal of Control, Measurement, and System Integration, Vol.6, No.6, pp.419-426 (2013)  (T&F, Open Access)

[6] H. Okajima, H. Umei, N. Matsunaga and T. Asai：A Design Method of Compensator to Minimize Model Error, SICE Journal of Control, Measurement, and System Integration, Vol.6, No.4, pp.267-275 (2013)  (T&F, Open Access) MECpage [Detail]

[5] H. Okajima and T. Asai：Performance Limitation of Tracking Control Problem for a Class of References, IEEE Transactions on Automatic Control, Vol.56, No.11, pp.2723-2727 (2011) SupportPage , PDF , [Detail]

[4] N. Matsunaga, A. T. Zengin, H. Okajima, and S. Kawaji：Emulation of Fast and Slow Pains using Multi-layered Sensor modeled the Layered Structure of Human Skin, Journal of Robotics and mechatronics, Vol.23, No.1, pp.239-247 (2011)

[3] C. L. Ooi, T. Asai and H. Okajima：Extension of Reference Signals in Iterative Learning Control for Non-Minimum Phase Systems, SICE Journal of Control Measurement and System Integration, Vol.4, No.1, pp.50-54 (2011)  (T&F, Open Access)

[2] H. Okajima, N. Matsunaga and S. Kawaji：Design of Dynamic Quantizers for 2-DOF IMC and Its Application to the Temperature Control of a Heat Plate, SICE Journal of Control Measurement and System Integration, Vol.4, No.1, pp.77-82 (2011)  (T&F, Open Access)

[1] T. Asai, H. Okajima and C. L. Ooi：Pole Constraints of Reference Models in 2-DOF Servo System Design for Non-Minimum Phase Systems, SICE Journal of Control Measurement and System Integration, Vol.1, No.6, pp.429-434 (2008)  (T&F, Open Access)

International Conference Paper

[69] T. Momose, H. Nishizato, K. Ishida, S. Oda, K. Nasu, L. Jin, H. Okajima,  Intelligent Sustainable ALD Research Platform Integrating On-Demand Precursor Delivery with in situ Imaging Ellipsometry, AVS 72nd International Symposium & Exhibition (2026) (abstract review)

[68] A. Fikri, N. Matsunaga and H. Okajima, Decentralized Dual-Layer Framework for Multi-Robot Exploration with Predictive Area Division and Redundancy-Aware Waypoint Sequencing, 2026 IEEE Region 10 Conference (2026)

[67] K. Ono, T. Hayashi, H. Okajima and N. Matsunaga, Minimum Data Length for Exact System Identification of Multirate SISO Systems via Cyclic Reformulation, 2026 SICE Festival with Annual Conference (2026)

[66] R. Iwai, N. Kurita, H. Okajima and N. Matsunaga, Path Following Control for Tracked Vehicles Based on Feedback Linearization with Track Velocity Dynamics, 2026 SICE Festival with Annual Conference (2026)

[65] H. Okajima, Model Error Compensator for adding Robustness toward Existing Control, Preprints of the IFAC World Congress, pp. 3998 - 4005 (2023)

[64]I. Yamamoto, K. Nakamura, N. Matsunaga and H. Okajima: Crowd Tracking of Electric Wheelchair using RGB-D Camera with Median of Candidate Vectors Observer, Proceedings of the SICE Annual Conference 2021 (2021)

[63]K. Fujinami and H. Okajima: Less-Conservative Reachable Set Estimation using Feedforward State Updating and Robust Invariant Set, Proceedings of the SICE Annual Conference 2020 pp. 1156-1158 (2020)

[62]Y. Take, S. Tokunaga, H. Okajima and N. Matsunaga: A Proposal of Collation Method Using Nonlinear SVM for Restoration of Stone Wall in Kumamoto Castle, Proceedings of the SICE Annual Conference 2020, pp. 888-893 (2020)

[61]R. Yoshida, Y. Tanigawa, H. Okajima and N. Matsunaga: A Design Method of Model Error Compensator using Meta-Heuristics and LMIs, Proceedings of the SICE Annual Conference 2020 pp. 1150-1155 (2020) MECpage

[60]Y. Takeuchi, N. Matsunaga and H. Okajima: Driving Instruction and Training of Welfare Vehicle controlled by Virtual Platoon Scheme using Sharing System of AR, 19th International Conference on Control, Automation and Systems, 1438-1443 (2019)

[59]T. Honda, N. Matsunaga and H. Okajima: Hybrid Steering Model depending on Driver's Gazing Point to detect inattentive driving using Machine Learning, 19th International Conference on Control, Automation and Systems, 1344-1349 (2019)

[58]K. Tanaka, S. Fukumoto, N. Matsunaga and H. Okajima:Obstacle Avoidance of Welfare Vehicle with Head Mounted Display using Spatial Mapping of Driving Environment, 19th International Conference on Control, Automation and Systems, 1222-1227 (2019)

[57] Shizuku Kai, Minori Watanabe and Hiroshi Okajima, Dynamics modeling of necessary quantity of relief supplies in large-scale disasters, Proceedings of the SICE Annual Conference 2019, pp.1044-1049 (2019)Finalist of the young author award

[56] Yusuke Take, Hiroshi Okajima, Nobutomo Matsunaga and Gou Koutaki, Restoration of Stone Wall “ISHIGAKI” Using Dropposition Information, Proceedings of the SICE Annual Conference 2019, pp.976-981 (2019)

[55] Hiroshi Okajima, Yohei Hosoe, Tomomichi Hagiwara and Yuki Minami, Basic Idea of Periodically Time-Varying Dynamic Quantizer in Networked Control Systems, Proceedings of the SICE Annual Conference 2019, pp.883-889 (2019)Finalist of the poster presentation award QUANTIZERpage

[54] Hiroshi Okajima, Yasuaki Kaneda and Nobutomo Matsunaga, State Estimation By Observer Using Median Operation for Observed Output with Outliers, Proceedings of the SICE Annual Conference 2019, pp.877-882 (2019)Finalist of the poster presentation award

[53] Nobutomo Matsunaga, Naufal Bayu Fauzan, Hiroshi Okajima and Gou Koutaki, Archive Method of Stone Wall in Kumamoto Castle Lifted by Small CMG Crane using Model Error Compensator, 2019 12th Asian Control Conference , 18849231 (2019)

[52] Nobutomo Matsunaga, Yudai Takeuchi and Hiroshi Okajima, Driver’s Gaze-point Analysis of Virtual Platoon Driving for Welfare Vehicle using Direct Eye Measurement Device with HMD, 2019 12th Asian Control Conference, 18834072 (2019)

[51] Shoichi Sakamoto, Nobutomo Matsunaga and Hiroshi Okajima, Hybrid Steering Model Estimated by Particle Swarm optimization Based on Driver’s Eye Tracking Information, 2018 18th International Conference on Control, Automation and Systems, Paper No.P00160 (2018)

[50] Yuta Nakabayashi, Hiroshi Okajima, Nobutomo Matsunaga, Inter-Vehicle Distance Stabilization in Adaptive Cruise Control Using Signal Limitation Filter, Proceeding of 2018 IEEE International Conference on Systems, Man, and Cybernetics, pp.1985-1990 (2018) MECpage

[49] Nobutomo Matsunaga, Ryota Kimura, Haruya Ishiguro, Hiroshi Okajima, Driving Assistance of Welfare Vehicle with Virtual Platoon Control Method which has Collision Avoidance Function Using Mixed Reality, Proceeding of 2018 IEEE International Conference on Systems, Man, and Cybernetics, pp.1911-1916 (2018)

[48] Shizuku Kai, Hiroshi Okajima, Time series modeling of evacuees for evacuation centers in large-scale disasters, Proceedings of the SICE Annual Conference 2018, pp.1148-1151 (2018)

[47] Yuki Tamura, Hiroshi Okajima, Nobutomo Matsunaga, Yasuaki Kaneda, Construction of new robust state estimation observer for packet loss environment, Proceedings of the SICE Annual Conference 2018, pp.1166-1168 (2018)

[46] Yuki Saigo, Hiroshi Okajima, Nobutomo Matsunaga, Design of networked control for multiple inputs and outputs feedback control system, Proceedings of the SICE Annual Conference 2018, pp.1423-1428 (2018) QUANTIZERpage

[45] S. Kimura, N. Matsunaga, H. Okajima and G. Koutaki：Design of virtual platoon control system using augmented reality to assist welfare vehicle users, Proceedings of ICCAS 2017 (2017) Outstanding Paper Award

[44] S. Sakamoto, T. Tanaka, H. Okajima and N. Matsunaga：Maneuverability evaluation of skid steer welfare vehicle for robust assistance control with model error compensator, Proceedings of ICCAS 2017 (2017)

[43] N. Matsunaga, H. Okajima and Y. Yamamoto：Robust variable stiffness control of McKibben type pneumatic artificial muscle arm by using multiple model error compensators, Proceedings of ICCAS 2017 (2017) 

[42] K. Kimura, N. Matsunaga and H. Okajima：Driving Assistance System forWelfare Vehicle using Virtual Platoon Control with Augmented Reality, Proceedings of the SICE Annual Conference 2017

[41] K. Inomoto, H. Okajima, G. Koutaki, N. Matsunaga and K. Uchimura：Method for designing a quantized image for digital micromirror device-based projectors using a weighted evaluation function, Proceedings of the SICE Annual Conference 2017 Finalist of the young author award

[40] Y. Nakabayashi, H. Okajima and N. Matsunaga：Signal limitation filter to satisfy velocity and acceleration constraints for arbitrary input signals, Proceedings of the SICE Annual Conference 2017 MECpage

[39] D. Matsuno, N. Matsunaga, Y. Shida and H. Okajima：Evaluation of steering model depending on gazing distance by using driving simulator, Proceedings of ICCAS 2016 (2016) Outstanding Paper Award

[38] T. Tanaka, H. Okajima and N. Matsunaga：Experiment of robust driving assistance control for skid steer welfare vehicle using model error compensator, Proceedings of ICCAS 2016 (2016) Outstanding Paper Award

[37] H. Okajima, Y. Minami and N. Matsunaga：Unilateral Control Structure Under Communication Rate Constraint, Proceedings of NecSys 2016 (6pages) (2016) QUANTIZERpage

[36] G. Ichimasa, K. Okumura, H. Okajima and N. Matsunaga：Extended structure of MEC for thermal process, Proceedings of the SICE Annual Conference 2016, pp.1593-1598 (2016) MECpage

[35] T. Sugano, H. Okajima, S. Samura and N. Matsunaga：Narrow space driving of welfare vehicles using robust platoon control with adaptive way point tracking, Proceedings of the SICE Annual Conference 2016, pp.1436-1441 (2016)

[34] H. Okajima, T. Asai and N. Matsunaga：Disturbance rejection performance limit for a class of disturbance signals, Proc. of the IEEE Conference on Decision and Control 2015, 2015.12

[33] G. Koutaki, H.Okajima, N. Matsunaga and K.Uchimura：Optimization of color quantization with total luminance for DLP projector and its evaluation system, ICIP2015 QUANTIZERpage

[32] T.Sugano, H.Okajima and N.Matsunaga：Robust and precise platoon driving control of welfare vehicles along wheel track by using model error compensator, IECON2015, YF-001503

[31] H. Okajima, T. Asai and N. Matsunaga：Analytical Solutions for Disturbance Rejection Problems using All Achievable Output Set for Stable Plants, SICE International Symposium on Control Systems 2015, 513-2, (2015.3)

[30] H. Okajima, M. Honda, R. Yoshino and N. Matsunaga：A design method of delta-sigma data conversion system with pre-filter, SICE Annual Conference 2014, pp.1388-1394, (2014.9) QUANTIZERpage

[29] R. Yoshino, H. Okajima, N. Matsunaga and Y. Minami：Dynamic quantizers design under data rate constraints by using PSO method, SICE Annual Conference 2014, pp.1041-1046, (2014.9) QUANTIZERpage

[28] T. Sugano, Y. Dan, H. Okajima, N. Matsunaga and Z. Hu：Indoor Platoon Driving of Electric Wheelchair with Model Error Compensator along Wheel Track of Preceding Vehicle, The 5th International Symposium on Advanced Control of Industrial Processes, 2014.5

[27] Y. Dan, H. Okajima, N. Matsunaga, Z. Hu and N. Nakamura：Experiment of Indoor Platoon Driving using Electric Wheelchair STAVi Controlled by Modeling Error Compensation System, ICT-PAMM Workshop on Mobility Assistance and Service Robotics, p26-31, 2013.11.

[26] K. Nabekura, H. Okajima, N. Matunaga and N. Nakamura：On Collision-Avoidance Steering Assistance of Piggyback Type Electric Wheelchair with Inference of Driver’s Intention, ICT-PAMM Workshop on Mobility Assistance and Service Robotics, p20-25, 2013.11.

[25] Y. Maruno, Y. Dan, A. T. Zengin, H. Okajima and N. Matsunaga：Maneuverability Analysis of Front Drive Type Personal Vehicle STAVi using Modeling Error Compensation System, 7th IFAC Symposium on Advanced in Automative Control, 2013.9.

[24] A. T. Zengin, Y. Maruno, H. Okajima and N. Matsunaga：Slope driving experiment of front drive type electric wheelchair with casters using yaw-rate compensation, ICCAS 2012, 2012.10.

[23] Y. Maruno, A. T. Zengin, H. Okajima,N. Matsunaga and N. Nakamura：Driving experiment of front drive type electric wheelchair using yaw-rate control, SICE Annual Conference 2012, WeA11-01 pp.1408-1413, 2012.8.

[22] A. T. Zengin, Y. Maruno, H. Okajima and N. Matsunaga：Improvement in Straight-ahead Stability of Front Drive Type Electric Wheelchair using Yaw-rate Control, VTI 2012, 2012.7.

[21] K. Sawada, H. Okajima, N. Matsunaga and Y. Minami：Dynamic quantizer design for MIMO systems based on communication rate constraint, IECON 2011, 2011.11.  QUANTIZERpage

[20] Y. Maruno, H. Okajima, A. T. Zengin and N. Matsunaga：Direct yaw moment control of front drive type electric wheelchair with free-casters, ICCAS 2011, 2011.10. Outstanding Award

[19] A. T. Zengin, H. Okajima and N. Matsunaga：On vibration feedback method for pain emulation and its feedback to human, ICCAS 2011, 2011.10. Finalist of Outstanding Award

[18] H. Umei, H. Okajima, N. Matsunaga and T. Asai：A design method of compensator to minimize model error, SICE Annual Conference 2011, 2011.9.  MECpage

[17] H. Okajima, K. Sawada and N. Matsunaga：Integrated Design of Filter and Interval in Dynamic Quantizer under Communication Rate Constraint, The 18th IFAC World Congress, 2011.8.  QUANTIZERpage

[16] N. Matsunaga, H. Okajima, T. Yoshida and S. Kawaji：Passivity evaluation of steering action with adjusting reaction torque to the driver, ASCC2011, 2011.5.

[15] H. Okajima, N. Matsunaga and K. Sawada：Optimal quantization interval design of dynamic quantizers which satisfy the communication rate constraints, Proc. of the IEEE Conference on Decision and Control 2010, 2010.12.  QUANTIZERpage

[14] N. Matsunaga, K. Sasano and H. Okajima：An implementation of fractional-order PID controller with dynamic quantizer considering the memory constraint, Proc. of the IEEE Multi-conference on Systems and Control 2010, 2010.9.  QUANTIZERpage

[13] H. Okajima, S. Yonaha, N. Matsunaga and S. Kawaji：Direct Yaw-moment Control method for electric vehicles to follow the desired path by driver, SICE Annual Conference 2010, 2010.8., Finalist of the young author award

[12] C. L. Ooi, T. Asai and H. Okajima：Extension of reference signal in iterative learning control for non-minimum phase systems, SICE Annual Conference 2010, 2010.8.

[11] A. T. Zengin, N. Matsunaga, H. Okajima and S. Kawaji：Pain perception model of human skin using multiple pain sensors, SICE Annual Conference 2010, 2010.8.

[10] H. Okajima, T. Asai and S. Kawaji：Unified form of performance limitations in reference tracking control problem for discrete time systems, Proc. of the 47th IEEE Conference on Decision and Control/CCC joint, 2009.12.

[9] N. Matsunaga, T. Shiotsuki, H. Okajima, N. Ohmura：Experiment of Measurement and Control using Embedded System for Undergraduate Students, the 8th IFAC Symposium on Advances in Control Education, Kumamoto, ThC01.5, 2009.10.

[8] H. Okajima, T. Umemoto, N. Matsunaga and S. Kawaji：Analysis of dynamic quantizer in 2-DOF Internal Model Control system with dead-time, Proc. of ICROS-SICE International Joint Conference 2009, pp.4380-4383, 2009.8.

[7] M. Nakano, N. Matsunaga, H. Okajima and S. Kawaji：Tuning of feedback type decoupling controller for two-dimensional thermal process based on VRFT method, Proc. of ICCAS-SICE International Joint Conference 2009, pp.925-930, 2009.8.

[6] N. Matsunaga, R. Mera, H. Okajima and S. Kawaji：Stifness Analysis of Crank Motion Task using Six-Muscles Model, Proc. of ICROS-SICE International Joint Conference 2009, pp.4478-4483, 2009.8.

[5] H. Okajima and T. Asai：Performance limitation of tracking control problem for a class of references, Proc. of the 47th IEEE Conference on Decision and Control, pp.3694-3699, 2008.12.

[4] H. Okajima, T. Asai and S. Kawaji：Optimal Velocity Control Method in Path Following Control Problem, Proc. of The 17th IFAC World Congress, pp.90-95, 2008.6.

[3] H. Okajima and T. Asai：Parameterization of Outputs Tracking to Reference Asymptotically and Achievable by Bounded Inputs, Proc. of The 32nd Annual Conference of the IEEE Industrial Electronics Society, pp.682-687, 2006.11.

[2] C. L. Ooi, H. Okajima and T. Asai：Constraints in Servo System Design for Non-Minimum Phase System, Proc. of Sice-Icase International Joint Conference 2006, pp.970-973, 2006.10.

[1] H. Okajima and T. Asai：Path-Following Control based on Trajectory Differences, Proc. of The 10th IFAC/IFORS/IMACS/IFIP Symposium on Large Scale Systems, pp.735-740, 2004.7.