Papers

近年の論文など一覧 (Current papers)


Recent awards

  • Sep 2024, AESJ-Materials Science Div., Young Researcher's Award, Yosuke NISHIMURA
  • Sep 2024, AESJ, Best Poster Award, Wen ZHOU
  • Aug 2024, ICONE31, Best Poster Award, Johndel OBRA
  • Aug 2024, ICONE31, Best Paper Award, Yihua XU
  • Aug 2024, ICONE31, Best Poster Award, Wen ZHOU
  • Aug 2024, ANS-Taiwan Section, Young Member Research Excellence Award, Shuichiro MIWA
  • Aug 2024, JSM, Best Presentation Award, Hanyu WANG
  • Aug 2024, JSM, Innovative Award, Ruicong XU
  • Mar 2024, AESJ, Best Presentation Award, Wen Zhou
  • Dec 2023, RSi Contest 2023, Grand Prize, Ryoma AOKI
  • Nov 2023, ISMTMF, Best Presentation Award, Ruicong XU
  • Nov 2023, SCOPE Conf., Best Paper Award, Zeeshan AHMED
  • Sep 2023, AESJ, Best Poster Award, Yosuke NISHIMURA
  • Sep 2023, AESJ, Best Poster Award, Atsushi NODA
  • May 2023, ICONE30, Akiyama Medal, Yosuke NISHIMURA
  • May 2023, ICONE30, Best Paper Award, Ruicong XU
  • May 2023, ICONE30, Best Poster Award, Weiyi YAO
  • May 2023, WM2023 Symposia, Superior Paper Award, Wei SHI
  • Mar 2023, Atomic Energy Society of Japan, Kanto-Koshinetsu Division, Young Researcher's Award, Yosuke Nishimura
  • Sep 2022, Atomic Energy Society of Japan, Special Poster Award for Experiment, Yosuke Nishimura
  • Jul 2022, Top 5 excellent researcher from young researchers under 35 years old. IAEA on R and D section, Ryo Yokoyama
  • Mar 2022, Best Presentation Award, NDEC-7, Ryo Yokoyama
  • Dec 2021, Best Presentation Award, IRID symposium, Ryo Yokoyama
  • Jul 2021, Best Presentation Award, 17 th JSME meeting oral, Ryo Yokoyama
  • Mar 2021, Best Frontier Spirit Award，NDEC-6, Ryo Yokoyama
  • Mar 2021, Best Presentation Award，AESJ spring meeting poster, Ryo Yokoyama
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      Year 2024

      Journal Publications

      [1] A. K. Sharma, W. Sagawa, Z. Ahmed, Y. Nishimura, K. Okamoto, Integrated experimental assessment and validation of oxidation with real-scale SiC fuel compact in HTGR, International Journal of Heat and Mass Transfer, Volume 220 (2024), ISSN 0017-9310.
      [2] W. Zhou, S. Miwa, K. Okamoto, Advancing fluid dynamics simulations: A comprehensive approach to optimizing physics-informed neural networks. Physics of Fluids, Vol. 36 (2024), 013615.
      [3] A. K. Sharma, R. Xu, Z. Ahmed, S. Miwa, S. Suzuki, A. Kosuge, Investigation of aerosol generation through laser cleaning of various surfaces and optimization of mist & spray scavenging, Journal of Aerosol Science, Vol. 177 (2024), 106329.
      [4] W. Zhou, S. Miwa, R. Tsujimura, T-B. Nguyen, T. Okawa, K. Okamoto, Bubble feature extraction in subcooled flow boiling using AI-based object detection and tracking techniques, International Journal of Heat and Mass Transfer, Vol. 222 (2024), 125188.
      [5] M. Yu, T. Hibiki, N. Tsukamoto, S. Miwa, Flow characteristics of dispersed two-phase flows in an 8x8 rod bundle, Experimental Thermal and Fluid Science, Vol. 153 (2024), 111146.
      [6] R. Xu, A. K. Sharma, E. Ozdemir, S. Miwa, S. Suzuki, Numerical investigation on improved spray system for efficient aerosol removal during the decommissioning of Fukushima Daiichi nuclear power plants, Nuclear Engineering and Design, Vol. 419 (2024), 112960.
      [7] D. Saito, Y. A. Prayitno, P.A. Sejati, S. Miwa, and M. Takei, Spatio-temporal Void Fraction Visualization in Air-Water Two-phase Flow Regime Transitions by Combination of Convolutional Neural Network and Long Short-Term Memory implemented into Multiple Current-Voltage (MCV-CNN_LSTM), Flow Measurement and Instrumentation, Vol. 97 (2024), 102593.
      [8] R. Xu, A. K. Sharma, E. Ozdemir, S. Miwa, S. Suzuki, Experimental investigation on effective aerosol scavenging using different spray configurations with pre-injection of water mist for Fukushima Daiichi decommissioning, Nuclear Science and Techniques, Vol. 35 (2024), Open Access
      [9] M. Pellegrini, K. Okamoto, B. Blaisot, N. Erkan, Investigation of jet induced by direct contact condensation using PIV, Nuclear Engineering and Design, Volume 424, 1 August 2024, 113312
      [10] W. Zhou, S. Miwa, K. Okamoto, Self-Adaptive and Time Divide-and-Conquer Physics-Informed Neural Networks for Two-Phase Flow Simulations Using Interface Tracking Methods, Physics of Fluids, Vol. 37 (2024), 073305.
      [11] R. Xu, A. K. Sharma, S. Miwa, S. Suzuki, Development of improved spray system with effective electrical electrodes for aerosol removal: An experimental study in UTARTS facility, Journal of Aerosol Science, Vol. 181 (2024), 106431
      [12] E. Ozdemir, R. Xu, S. Miwa, S. Suzuki, K. Okamoto, Numerical and experimental approach for dust dispersion and deposition behavior for safe decommissioning activities, Energy Sources, Part A, Vol. 46 (2024), 8070-8087.
      [13] W. Zhou, S. Miwa, H. Wang, K. Okamoto, Assessment of the State-of-the-Art AI Methods for Critical Heat Flux Prediction, International Communications in Heat and Mass Transfer, Vol. 158 (2024), 197844.
      [14] S. Wang, K. Wang, S. Miwa, T. Chen, K. Okamoto, A Dynamic Characteristics on the Boiling Crisis in Downward facing Flow Boiling, Part I: Motion of the CHF Front and Factors Investigation, International Communications in Heat and Mass Transfer, Vol. 159 (2024), 108035.
      [15] W. Zhou, S. Miwa, K. Eguchi, S. Yamashita, K. Okamoto, Development of Advanced AI-Based Segmentation and Prediction Method for Air Entrainment in Plunging Water Jets, Progress in Nuclear Energy, Vol. 177 (2024), 105441.
      [16] Y. Nishimura, A. Gubarevich, K. Yoshida, K. Okamoto, An Innovative Fuel Design for HTGRs: Evaluating a 10-Hour High-Temperature Oxidation of the SiC Fuel Matrix During Air Ingress Accident Conditions, Energies, Vol. 17 (2024), 5366.
      [17] R. Xu, A. K. Sharma, S. Miwa, S. Suzuki, Improvement of aerosol spray scavenging efficacy by pre-injecting electrically charged water mist, Journal of Environmental Chemical Engineering, (Accepted)
      [18] S. Wang, K. Wang, S. Miwa, T. Chen, K. Okamoto, A Dynamic Characteristics on the Boiling Crisis in Downward facing Flow Boiling, Part II: Model Development and Validation, International Communications in Heat and Mass Transfer, (Accepted)

      Conferences

      [1] A. Nappi, M. Pellegrini, Modelling of the LIVE-J experiment with CFD and MELCOR, 2024 Korea-Japan Bilateral Workshop on Nuclear Safety Information Exchange, Seoul National University, Seoul, Korea, January 25-27, 2024.
      [2] R. Yokoyama, R&D of A Novel Particle Method “Moving Particle Hydrodynamics” for Nuclear Severe Accident Analyses and Fukushima Daiichi NPP Decommissioning, 2024 Korea-Japan Bilateral Workshop on Nuclear Safety Information Exchange, Seoul National University, Seoul, Korea, January 25-27, 2024.
      [3] R. Xu, A.K. Sharma, E. Ozdemir, H. Laffolley, S. Miwa, S. Suzuki, Efficient Aerosol Control and Removal for Fukushima Daiichi Decommissioning Study on spray scavenging of aerosols in UTARTS facility, 2024 Korea-Japan Bilateral Workshop on Nuclear Safety Information Exchange, Seoul National University, Seoul, Korea, January 25-27, 2024.
      [4] W. Zhou, S. Miwa, K. Okamoto, R. Tsujimura, B. Nguyen, T. Okawa, Robust condensation bubble feature extraction in subcooled flow boiling using object detection and tracking technique, 2024 Korea-Japan Bilateral Workshop on Nuclear Safety Information Exchange, Seoul National University, Seoul, Korea, January 25-27, 2024.
      [5] S. Wang, T. Chen, K. Wang, S. Miwa, K. Okamoto, A Dynamic Characteristics on the Boiling Crisis in Downward-facing Flow Boiling, 2024 Korea-Japan Bilateral Workshop on Nuclear Safety Information Exchange, Seoul National University, Seoul, Korea, January 25-27, 2024.
      [6] J. Obra, S. Miwa, Accident analysis of Nuclear Reactors using AI, 2024 Korea-Japan Bilateral Workshop on Nuclear Safety Information Exchange, Seoul National University, Seoul, Korea, January 25-27, 2024.
      [7] M. Pellegrini, Latest Trends in the Japanese Nuclear Power Industry, 2024 Korea-Japan Bilateral Workshop on Nuclear Safety Information Exchange, Seoul National University, Seoul, Korea, January 25-27, 2024.
      [8] S. Miwa, Introducing UTokyo's Nuclear Enigneering Program and R&D Status, 2024 Korea-Japan Bilateral Workshop on Nuclear Safety Information Exchange, Seoul National University, Seoul, Korea, January 25-27, 2024.
      [9] R. Xu, A.K. Sharma, S. Miwa, S. Suzuki, Development of the electrical spray charging system for aerosol control in Fukushima Daiichi decomissioning, The Ninth Conference for R&D Initiative on Nuclear Decommissioning Technology by the Next Generation (NDEC-9), Fukushima, Japan, March 21-22, 2024.
      [10] Y. NISHIMURA, A. GUBAREVICH, K. YOSHIDA, K. TAKAMATSU and K. OKAMOTO, Multiphysics Behavior in HTGRs with High Power Density (1) Accident Behaviors of Fuel Matrices, Atomic Energy Society of Japan 2024 Annual Meeting, Kindai University, March 26-28, 2024.
      [11] K. Takamatsu, S. Okita, Y. Tachibana, Y. Nishimura and K. Okamoto, Multiphysics Behavior in HTGRs with High Power Density (2) Feasibility Study, Atomic Energy Society of Japan 2024 Annual Meeting, Kindai University, March 26-28, 2024.
      [12] K. Okamoto, K. Tanaka, Develop global human resources to oversee decommissioning of nuclear facilities (1) Purpose and significance of developing global human resources to oversee decommissioning of nuclear facilities, Atomic Energy Society of Japan 2024 Annual Meeting, Kindai University, March 26-28, 2024.
      [13] K. Tanaka, K. Okamoto, Develop global human resources to oversee decommissioning of nuclear facilities (2)Outline of Human Resource Development Program, Atomic Energy Society of Japan 2024 Annual Meeting, Kindai University, March 26-28, 2024.
      [14] S. Miwa, A.K. Sharma, R. Xu, S. Suzuki, A. Kosuge, K. Shibata, Research on Radioactive Aerosol Control and Decontamination at Fukushima Daiichi Nuclear Power Station Decommissioning (1) Evaluation of aerosol scattering under laser decontamination, Atomic Energy Society of Japan 2024 Annual Meeting, Kindai University, March 26-28, 2024.
      [15] A.K. Sharma, S. Miwa, R. Xu, S. Suzuki, A. Kosuge, Research on Radioactive Aerosol Control and Decontamination at Fukushima Daiichi Nuclear Power Station Decommissioning (2) Characterization and scavenging of aerosols generated by Laser cleaning experiment, Atomic Energy Society of Japan 2024 Annual Meeting, Kindai University, March 26-28, 2024.
      [16] R. Xu, A.K. Sharma, S. Miwa, S. Suzuki, Research on Radioactive Aerosol Control and Decontamination at Fukushima Daiichi Nuclear Power Station Decommissioning (3) Development of the electro-scavenging technique using multi-scale charged spray droplets, Atomic Energy Society of Japan 2024 Annual Meeting, Kindai University, March 26-28, 2024.
      [17] K. SHIBATA, A. K. SHARMA, R. XU, S. MIWA, S. SUZUKI, A. KOSUGE, D. MEGSON-SMITH, T. BENNETT, T. SCOTT, Research on Radioactive Aerosol Control and Decontamination at Fukushima Daiichi Nuclear Power Station Decommissioning (4) Summary and achievement of UK-Japan joint experiment at mock-up facility, Atomic Energy Society of Japan 2024 Annual Meeting, Kindai University, March 26-28, 2024.
      [18] W. Zhou, S. Miwa, K. Okamoto, Physics-Informed Neural Networks for Two-Phase Flow Simulations: An Integrated Approach with Advanced Interface Tracking Methods, Atomic Energy Society of Japan 2024 Annual Meeting, Kindai University, March 26-28, 2024.
      [19] J. B. Obra, S. Miwa, K. Okamoto, Development of LSTM models for the combined forecasting and diagnosis of PWR LOCA accident events, Atomic Energy Society of Japan 2024 Annual Meeting, Kindai University, March 26-28, 2024.
      [20] W. Zhou, S.Miwa, K. Okamoto, Physics-Informed Neural Networks for Two-Phase Flow Simulations: An Integrated Approach with Advanced Interface Tracking Methods, The Japanese Society for Artificial Intelligence, 2024年度人工知能学会全国大会（第38回）, May 28 - 31, 2024.
      [21] 山内 大典, 戸塚 文夫, 茂木一貴, 岩田裕一 , 三輪修一郎, 鈴木俊一, 岡本孝司, 燃料デブリ取り出し時のダスト飛散挙動推定に向けた研究,　 Visualization　Symposium in Okinawa 2024　(VSJ OKINAWA 2024), July 19-21, 2024.
      [22] F. Yang, S. Li, M. Takei and S. Miwa, Analysis of microstructure of cream structure reflected in Bubble Void Fraction by Electrical impedance Tomograph combine with machine learning, Visualization　Symposium in Okinawa 2024　(VSJ OKINAWA 2024), July 19-21, 2024.
      [23] J. Obra, S. Miwa, Investigation of Lstm and Automl-Based Models for the Real-Time Diagnosis of Pwr Loca Accident Progression, The 31st International Conference on Nuclear Engineering (ICONE31), Prague, Czech Republic, August 4-8, 2024. [Best Poster Award]
      [24] W. Zhou, R. Tsujimura, S. Miwa, T. Okawa, K. Okamoto, The Robust Development of a Thermal Hydraulic Analysis Method for Condensation Bubbles in Subcooled Flow Boiling Using AI Based Object Detection and Tracking Technique, The 31st International Conference on Nuclear Engineering (ICONE31), Prague, Czech Republic, August 4-8, 2024. [Best Poster Award]
      [25] S. Wang, K. Wang, S. Miwa, K. Okamoto, Analyzing Flow Rate Impact on Chf Front Behavior During Boiling Crisis in Downward Flow Boiling, The 31st International Conference on Nuclear Engineering (ICONE31), Prague, Czech Republic, August 4-8, 2024.
      [26] R. Xu, A. K. Sharma, H. Laffolley, S. Miwa, S. Suzuki, Experimental study of enhanced spray scavenging of laser-generated aerosol particles by pre-injecting charged water mist, The 20th Conference on Japan Society of Maintenology, August 5-8, 2024. [Innovative Award]
      [27] H. Wang, S. Miwa, W. Zhou, T. Hibiki, K. Okamoto, Industry-applicable two-phase flow regime identification approach development using two-phase FIV signals, The 20th Conference on Japan Society of Maintenology, August 5-8, 2024. [Presentation Award]
      [28] R. Xu, A.K.Sharma, S. Miwa, S. Suzuki, K. Okamoto, Experimental Investigation on Aerosol Scavenging by Electrically Charged Spray with Preinjected Water Mist for Fukushima Daiichi decommissioning, The 14th International Topical Meeting on Nuclear Reactor Thermal-Hydraulics, Operation, and Safety (NUTHOS-14), August 25-28, 2024.
      [29] W. Zhou, S. Miwa, K. Okamoto, Physics-informed Neural Networks for Two-phase Flow Simulations: An Integrated Approach with Advanced Interface Tracking Methods, The 14th International Topical Meeting on Nuclear Reactor Thermal-Hydraulics, Operation, and Safety (NUTHOS-14), August 25-28, 2024.
      [30] S. Miwa, Transforming Nuclear Thermal-Hydraulics: Insights from Decommissioning, Multiphase Flow, and Machine Learning within the Carbon-Neutral Paradigm, National Tsing Hua University, Hsinchu, Taiwan, August 29, 2024. [Invited Seminar]
      [31] S. Miwa, Transforming Nuclear Thermal-Hydraulics: Insights from Decommissioning, Multiphase Flow, and Machine Learning within the Carbon-Neutral Paradigm, Annual Meeting of ANS-Taiwan, National Atomic Research Institute, Taiwan, August 30, 2024. [Invited Talk]
      [32] W. Zhou, S. Miwa, K. Okamoto, BF-GAN: Development of an AI-driven Bubbly Flow Image Generation Model Using Bubbly Generative Adversarial Networks, Atomic Energy Society of Japan 2024 Fall Meeting, Tohoku University, September 11-13, 2024. [Best Poster Award]
      [33] Y. Nishimura, Y. Yamazaki, K. Okamoto, Development of innovative design of HTGRs, Atomic Energy Society of Japan 2024 Fall Meeting, Tohoku University, September 11-13, 2024.
      [34] R. Yokoyama, S. Miwa, K. Okamoto, A Fully Explicit GPU-Accelerated DEM-MPH Method for Simulating Debris Bed Formation with Micro Scale Debris, Atomic Energy Society of Japan 2024 Fall Meeting, Tohoku University, September 11-13, 2024.


      Year 2023

      Journal Publications

      [1] M. Allaf, K. Okamoto, S. Suzuki, N. Erkan, Conceptualization of the micro research reactor cooled by heat pipes (MRR-HP), part-II: safety analyses, Journal of Nuclear Science and Technology. 01/10/2023. https://doi.org/10.1080/00223131.2022.2159560
      [2] Y. Yamamoto, N. Kitahara, F. Miyazawa, G. Chiba, S. Miwa, M. Mori, Level swell analysis of stagnant water pool in filtered containment venting systems, Progress in Nuclear Energy, Vol. 155 (2023), 104491.
      [3] W. Zhou, G. Sun, S. Miwa, Z. Yang, Z. Li, D. Zhang, J. Wang, An intelligent optimization method for the HCSB blanket based on an improved multi-objective NSGA-III algorithm and an adaptive BP neural network, Nuclear Engineering and Technology, Vol. 55 (2023), Pages 3150-3163
      [4] A. K. Sharma, H. Liang, R. Xu, E. Ozdemir, S. Miwa, R. Terabayashi, S. Suzuki, M. Pellegrini, S. Hasegawa & N. Erkan, Radioactive Aerosol Control and Decontamination in the Decommissioning of the Fukushima Daiichi Nuclear Power Station, Nuclear Technology, 209 (2023), 2030-2043, DOI: 10.1080/00295450.2023.2186675
      [5] K. Eguchi, S. Miwa, K. Sawa, Image analysis based on convolutional neural networks for flow regime identification of vertical upward two-phase flows , Japanese Journal of Multiphase Flow, Vol. 37 (2), 197-215
      [6] A. K. Sharma, R. Xu, Z. Ahmed, S. Miwa, B. Blaisot, S. Suzuki, H. Liang, N. Erkan, Scavenging of laser-generated aerosols with electrostatic-charged spray droplets, Journal of Aerosol Science, Vol. 174 (2023), 106254.
      [7] Y. Nishimura, A. Gubarevich, K. Yoshida, K. OKAMOTO, Comparison of SiC and graphite oxidation behavior under conditions of HTGR air ingress accident, Mechanical Engineering Letters, Vol. 8 (2022), Pages 22-00315
      [8] E. Ozdemir, S. Miwa, E. Porcheron, S. Suzuki, Koji Okamoto, Aerosol deposition and dispersion during nuclear reactor decommissioning, Nuclear Engineering and Design, Vol. 414 (2023), 112623
      [9] Y. Nishimura, A. Gubarevich, K. Yoshida, A.K. Sharma, K. Okamoto, Kinetic modeling of IG-110 oxidation in inert atmosphere with low oxygen concentration for innovative high-temperature gas-cooled reactor applications, Journal of Nuclear Science and Technology, Vol. DOI: 10.1080/00223131.2023.2274928
      [10] R. Yokoyama, M. Kondo, S. Suzuki, C. Journeau, M. Pellegrini, K. Okamoto, Evaluation of Molten Corium Spreading and Sedimentation Behaviors within Primary Containment Vessel in Unit 3 of Fukushima Daiichi Nuclear Power Plants towards the Best Prediction of Fuel Debris Distribution, Nuclear Technology, 2023 (In press), DOI:10.1080/00295450.2023.2262255

      Conferences

      [1] M. Pellegrini, N. Erkan, S. Miwa, K. Okamoto, Characterization of steam chugging by experimental and computational analyses. CFD4NRS-9 & OECD Nuclear Energy Agency Workshop, College Station, Texas, USA, February 20-21, 2023.
      [2] Erdal Ozdemir, Marco Pellegrini, Avadhesh Kumar Sharma, Shuichiro Miwa, Shunichi Suzuki, Koji Okamoto. A CFD approach to simulation of particle deposition for nuclear power plant safety. CFD4NRS-9 & OECD Nuclear Energy Agency Workshop, College Station, Texas, USA, February 20-21, 2023.
      [3] Avadhesh Kumar Sharmaa, Wataru Sagawaa, Yosuke Nishimurab, Koji Okamotoa, Verification & validation of multi-physical behavior in high-temperature gas-cooled reactor. CFD4NRS-9 & OECD Nuclear Energy Agency Workshop, College Station, Texas, USA, February 20-21, 2023.
      [4] Weiyi Yao, Marco Pellegrini, Ozdemir Erdal, Koji Okamoto, CFD investigation on single bubble rising hydrodynamics and wall effect during pool scrubbing. CFD4NRS-9 & OECD Nuclear Energy Agency Workshop, College Station, Texas, USA, February 20-21, 2023.
      [5] W. Shi, K. Okamoto, Inverse Estimation Study for Reconstructing Radioactive Source Distribution based on Least Absolute Shrinkage and Selection Operator (LASSO), Waste Management Conference 2023, Phoenix, AZ, USA, February 26-March 2, 2023. [Superior Paper Award]
      [6] K. Eguchi, S. Miwa, K. Sawa, Development of a gas-liquid two-phase flow image analysis method using deep learning based object detection and recognition techniques. AESJ Spring Meeting, The University of Tokyo, Komaba, Tokyo, Japan, March 13-15, 2023.
      [7] Y. A. K. Prayitno, D. Saito, S. Miwa, M. Takei, Visualization of spatio-temporal void fraction of vertical gas-liquid two-phase flow by coupled multiple current-voltage with wire-mesh sensor and convolutional neural network (MCV-WMS-CNN), 11th International Conference on Multiphase Flow, ICMF 2023, Kobe, Japan, April 2-7, 2023.
      [8] M. Pellegrini, S. Miwa, S. Suzuki, K. Okamoto, Multiphase-CFD Simulation of Steam Chugging by the Volume of Fluid Method, 11th International Conference on Multiphase Flow, 11th International Conference on Multiphase Flow, ICMF 2023, Kobe, Japan, April 2-7, 2023.
      [9] T. Chen, M. Pellgrini, Z. Hong, S. Miwa, K. Wang, K. Okamoto, Effects of the ITO glass on the critical heat flux and boiling phenomena in a downward-faced flow boiling, 11th International Conference on Multiphase Flow, ICMF 2023, Kobe, Japan, April 2-7, 2023.
      [10] A. K. Sharma, E. Ozdemir, R. Xu, S. Miwa, S. Suzuki, Spray Characterization using Shadowgraphy for Spray Nozzles, 11th International Conference on Multiphase Flow, ICMF 2023, Kobe, Japan, April 2-7, 2023.
      [11] S. Miwa, The Role of Nuclear Thermal hydraulics towards Carbon Neutrality: from Drift flux Model to Deep Learning, 11th International Conference on Multiphase Flow, ICMF 2023, Kobe, Japan, April 2-7, 2023. [Keynote Lecture]
      [12] R. Xu, A.K. Sharma, E. OZdemir, S. Miwa, S. Suzuki, M. Pellegrini, Investigation on Aerosol Spray Scavenging by Using a Multi-hole Nozzle with Water Mist for Decommissioning of Fukushima Daiichi Power Plants, 30th International Conference on Nuclear Engineering (ICONE30), Kyoto, Japan, May 21-26, 2023. [Best Paper Award]
      [13] Y. Nishimura, A. Gubarevich, K. Yoshida, K. Okamoto, EXPERIMENTAL STUDY ON SIC OXIDATION BEHAVIOR UNDER HTGR AIR INGRESS ACCIDENT, 30th International Conference on Nuclear Engineering (ICONE30), Kyoto, Japan, May 21-26, 2023. [Akiyama Medal Award]
      [14] S. Y. Choobak, D. Saito, Y. A. K. Prayitno, S. Miwa, M. Takei, 2D SPATIAL/ 1D TEMPORAL VOID FRACTION ANALYSIS OF VERTICAL UPWELLING FLOW USING MULTIPLE CURRENT-VOLTAGE AND CONVOLUTIONAL, 30th International Conference on Nuclear Engineering (ICONE30), Kyoto, Japan, May 21-26, 2023. [Best Poster Award]
      [15] W. Yao, M. Pellegrini, K. Okamoto, VALIDATION OF SPARC-90 POOL SCRUBBING MODEL IN SEVERE ACCIDENT CODE, 30th International Conference on Nuclear Engineering (ICONE30), Kyoto, Japan, May 21-26, 2023. [Best Poster Award]
      [16] E. Ozdemir, A. K. Sharma, S. Miwa, K. Okamoto, S. Suzuki, Visualization of a DisturbedWave Falling Film, 15th International Symposium on Particle Image Velocimetry ? ISPIV 2023, , San Diego, California, USAm June 19?21, 2023.
      [17] R. Yokoyama, International Young Professional in Decommissioning. Japanese Representative “Motivation to pursue the career in decommissioning, International Conference on Nuclear Decommissioning, Addressing the Past and Ensuring the Future, Vienna, May 15-19, 2023.
      [18] R. Yokoyama, Summary and Outcome of Young Generation Session, Nuclear Back End Webinar Series IAEA: Outcome of International Conference on Nuclear Decommissioning, Online, June 21, 2023
      [19] M. Pellegrini, Preliminary comparison of Task 1c MCCI sensitivity analyses, Convocation of the Third Meetings of the Programme Review Group and Management Board of the OECD/NEA FACE Project, Paris, France, June 28-30, 2023.
      [20] S. Miwa, Radioactive aerosol control and decontamination in the decommissioning of the FDNPS, Convocation of the Third Meetings of the Programme Review Group and Management Board of the OECD/NEA FACE Project, June 28-30, 2023, Paris, France.
      [21] S. Miwa, K. Eguchi, Two-phase flow regime identification using machine learning techniques, 20th International Symposium on Flow Visualization, Delft, the Netherlands, JULY 10-13, 2023.
      [22] E. Ozdemir, S. Miwa, M. Pellegrini, Thermophoretic Particle Deposition: A Computational Fluid Dynamics Approach for Assessing Hotspots, 20th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-20), Washington Hilton, Washington, DC, USA, August 20-25, 2023.
      [23] A.K. Sharma, R. Xu, Z. Ahmed, E. Ozdemir, S. Miwa,Aerosol Generation by Continuous Fiber Laser Irradiation of Various Surfaces and Spray Scavenging, 20th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-20), Washington Hilton, Washington, DC, USA, August 20-25, 2023.
      [24] S. Miwa, Two-Phase Flow-Induced Vibration in Various Flow Regimes, 20th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-20), Washington Hilton, Washington, DC, USA, August 20-25, 2023. [Keynote Lecture]
      [25] S. Miwa, K. Eguchi, Integration of AI Technology and Thermal Hydraulics for the Development of a Data-Driven Methodology for Plant Safety Assessment, (1) Evaluation of Flow Regime Transition in Vertical Upward Two-Phase Flow using Deep Learning, AESJ Fall Meeting, Nagoya University, Nagoya, Japan, September 6-8, 2023.
      [26] R. Tsujimura, T. Binh, T. Okawa, W. Zhou, S. Miwa, Integration of AI Technology and Thermal Hydraulics for the Development of a Data-Driven Methodology for Plant Safety Assessment, (2) Interference between nucleation sites in subcooled flow boiling and application of AI image analysis, AESJ Fall Meeting, Nagoya University, Nagoya, Japan, September 6-8, 2023.
      [27] S. Yamashita, W. Zhou, S. Miwa, Integration of AI Technology and Thermal Hydraulics for the Development of a Data-Driven Methodology for Plant Safety Assessment, (4) Bubble Entrainment Analysis by Water Jet using JUPITER code and Estimation of Penetration Length by Machine Learning, AESJ Fall Meeting, Nagoya University, Nagoya, Japan, September 6-8, 2023.
      [28] J. Obra, S. Miwa, Integration of AI Technology and Thermal Hydraulics for the Development of a Data-Driven Methodology for Plant Safety Assessment, (5) Investigation of LSTM models for the prediction of LOCA accident events, AESJ Fall Meeting, Nagoya University, Nagoya, Japan, September 6-8, 2023.
      [29] K. Aragane, T. Kitao, N. Tanaka, M. Mori, S. Miwa, Integration of AI Technology and Thermal Hydraulics for the Development of a Data-Driven Methodology for Plant Safety Assessment, (6) Parameter analysis for LWR accident by deep neural networks using CNN and Transformer, AESJ Fall Meeting, Nagoya University, Nagoya, Japan, September 6-8, 2023.
      [30] A. Zeeshan, A. K. Sharma, M. Pellegrini, H. Yamano, K. Okamoto, Visualization experiments of radiation heating on the eutectic reaction between B4C-SS and its relocation behavior, Saudi International Conference on Nuclear Power Engineering (SCOPE), King Fahd University of Petroleum & Minerals in Saudi Arabia, November 13-15, 2023. [Best Paper Award]
      [31] R. Xu, A. K. Sharma, E. Ozdemir, S. Miwa, S. Suzuki, Experimental study on aerosol removal using electrically charged spray scavenging, ISMTMF, Tokyo Institute of Technology, Tokyo, Japan, Novmberr 28-30, 2023. [Best Presentation Award]
      [32] R. Aoki, N. Matsuhira, S. Suzuki, H. Asama, S. Miwa, Collaborative Operation of External Sensors and Mobile Robots Using RSNP, The RSi Contest 2023, The System Integration Division Conference, The Society of Instrument and Control Engineers, Toki Messe, Niigata, Japan, December 14-16, 2023. [Grand Prize]


      Year 2022

      Journal Publications

      [1] A.K. Sharma, M. Pellegrini, K. Okamoto, M. Furuya, S. Mizokami, Validation and application of numerical modeling for in-vessel melt retention in corium pools, International Journal of Heat and Mass Transfer, vol. 196, pp. 123313, 2022. https://doi.org/10.1016/j.ijheatmasstransfer.2022.123313
      [2] R. Yokoyama, M. Kondo, S. Suzuki, K. Okamoto, Simulating melt spreading into shallow water using moving particle hydrodynamics with turbulence model.?Computational Particle Mechanics (2022). (In press) https://doi.org/10.1007/s40571-022-00520-7
      [3] R. Yokoyama, M. Kondo,?S. Suzuki, M. Johnson, S. Miwa, M. Pellegrini, A. Denoix, V. Bouyer, C. Journeau, K. Okamoto,?A Lagrangian approach to ex-vessel corium spreading over ceramic and concrete substrates using moving particle hydrodynamics, Nuclear Engineering and Design (2022), (In Press)
      [4] M. Allaf, K. Okamoto, N. Erkan. “Conceptual Design of the Multi-Purpose Micro Research Reactor Cooled by Heat-Pipes (MRR-HP) Part-I: neutronics analyses”, Journal of Nuclear Science and Technology. Published online 08/21/2022, https://doi.org/10.1080/00223131.2022.2098197
      [5] M. Allaf, S. ?enturk Lule, U. Colak, “ The Investigation of the Sensitivity of Monte Carlo Simulation Results to Modelling Approaches for Nuclear Reactor Cores,” European Journal of Science and Technology, August 31, 2022, Volume , Issue 38, 110 ? 115, https://doi.org/10.31590/ejosat.1065944
      [6] T. Ozaki, T. Hibiki, and S. Miwa, Sensitivity analysis using improved two-fluid model-based 1D code with the state-of-the-art constitutive equations for two-phase flow in rod bundle, Experimental and Computational Multiphase Flow, Vol. 4 (2022), 350-359.
      [7] S. Miwa and T. Hibiki, Inverted annular two-phase flow in multiphase flow systems, International J. Heat and Mass Transfer, Vol. 186 (2022) https://doi.org/10.1016/j.ijheatmasstransfer.2021.122340
      [8] T. Hibiki, P. Ju, J. Zhao, S. Miwa, Channel size effect on drift-flux parameters for adiabatic and boiling two-phase flows, IJHMT, Vol. 185 (2022) https://doi.org/10.1016/j.ijheatmasstransfer.2021.122410
      [9] S. Miwa, T Hibiki, K. Katono, Performance evaluation of drift-flux correlations in tight-lattice rod bundles, International Journal of Heat and Mass Transfer, Vol. 191 (2022), https://doi.org/10.1016/j.ijheatmasstransfer.2022.122664.
      [10]N. Shibata, S. Miwa, K. Sawa, T. Murayama, M. Takahashi and N. Tenma, Identification of high-pressure two-phase flow regime transition using image processing and deep learning” Journal of Natural Gas Science and Engineering, Vol. 102 (2022) https://doi.org/10.1016/j.jngse.2022.104560.
      [11]N. Shibata, S. Miwa, K. Sawa, T. Murayama, M. Takahashi and N. Tenma, Unsupervised Learning for Classification of Flow Regime in High-Pressure Gas-Liquid Two-Phase Flow Including Transition Region” Transactions of the JSME, Vol. 88 (2022) https://doi.org/10.1299/transjsme.21-00307
      [12]K. Katono, S. Miwa, and T. Hibiki, Experimental Investigation of Rod Pitch Effect on Void Fraction in 5× 5 Rod‐bundle under Elevated Pressure Conditions, International Journal of Heat and Mass Transfer, Vol. 195 (2022), https://doi.org/10.1016/j.ijheatmasstransfer.2022.123035

      Conferences

      [1] A.K. Sharma, H. Liang, S. Miwa, N. Erkan, S. Suzuki, R. Terabayashi, M. Pellegrini,
      Radioactive aerosol control and decontamination in the decommissioning for nuclear power plant,
      2022 Japan-US seminar on two-phase flow dynamics, May 8-11, 2022.
      [2]A.K. Sharma, B. Blaisot, M. Pellegrini, T. Saito, N. Erkan, K. Okamoto,
      Experimental investigation of particle removal efficiency using ethanol during the pool scrubbing,
      International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-19), Brussels, Belgium, March 6 - 11, 2022.
      [3] A.K. Sharma, M. Pellegrini, T. Saito, N. Erkan, K. Okamoto,
      Numerical analysis to evaluate the initial bubble size and bubble rising velocity during pool scrubbing,
      International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-19), Brussels, Belgium, March 6 - 11, 2022.
      [4] H. Liang, N. Erkan, K. Wang, A.K. Sharma, S. Suzuki,
      Numerical simulation of aerosol generation and aerosol spray Scavenging during Fukushima Daiichi decommissioning,
      29th Int. Conf. on Nuclear Engineering (ICONE29), China, August 8-12, 2022.


      Year 2021

      Journal Publications

      [1]R. Yokoyama, M. Kondo, S. Suzuki, K. Okamoto, Analysis of molten metal spreading and solidification behaviors utilizing moving particle full-implicit method, Frontiers in Energy, 15, pp 959-973, 2021.
      [2]R. Yokoyama, M. Kondo, S. Suzuki, M. Harada, Koji Okamoto, Investigation of the outflow and spreading-solidification behavior of stratified molten metal, Journal of Nuclear Engineering, 2(2), pp168-189, 2021. https://doi.org/10.3390/jne2020017


      Year 2020

      Journal Publications

      [1]L. Wang, K. Wang, N. Erkan, Y. Yuan, G. Chen, B. Nie, F. Li, K. Okamoto, Metal material surface wettability increase induced by electron beam irradiation, Applied Surface Science, Vol. 511, 145555, (2020)
      [2]L. Wang, Y. Yuan, N. Erkan, F. Li, K. Okamoto, Effect of metal honeycomb structure on enhancing CHF in saturated downward-facing flow boiling, Int. J. Heat and Mass Transfer, Vol. 149, 119244, (2020)
      [3]K. Wang, N. Erkan, K. Okamoto, A study on the effect of oxidation on critical heat flux in flow boiling with downward-faced carbon steel, Int. J. Heat Mass Transfer, Vol.147, 118966 (2020)
      [4]B. Jo, N. Erkan, K. Okamoto, Richardson number criteria for direct-contact-condensation- induced thermal stratification using visualization, Progress in Nuclear Energy, Vol.118, 103095, (2020)
      [5]K. Wang, N. Erkan, K. Okamoto, Effect of finned structure on critical heat flux (CHF) in downward-face pool boiling.Mechanical Engineering Journal. (2020) 19-00500.
      [6]K. Wang, H. Gong, L. Wang, N. Erkan, K. Okamoto. Effects of a porous honeycomb structure on critical heat flux in downward-facing saturated pool boiling. Appl. Therm. Eng., 166 (2020) 115036
      [7]M. Pellegrini, L. Herranz, M. Sonnenkalb, T. Lind, Y. Maruyama, R. Gauntt, N. Bixler, A. Morreale, K. Dolganov, T. Sevon, D. Jacquemain, C. Journeau, J. H. Song, Y. Nishi & S. Mizokami, Main Findings, Remaining Uncertainties and Lessons Learned from the OECD/NEA BSAF Project, Nuclear Technology (2020)
      [8]M.A. Allaf, S. Şentürk Lüle, Ü. Çolak, The development of TM2-RIA code for TRIGA type research reactors, Annals of Nuclear Energy, Volume 145, (2020)
      [9]R. Yokoyama, S. Suzuki, K. Okamoto, M. Harada, Scale effect of the amount of the molten metal and the outlet diameters for corium spreading,Progress in Nuclear Energy, 130, 103535, 2020.https://doi.org/10.1016/j.pnucene.2020.103535


      Year 2019

      Journal Publications

      [1] S. Bechta, W. Ma, A. Miassoedov, C. Journeau, K. Okamoto, D. Manara, D. Bottomley, M. Kurata, B. Sehgal, J. Stuckert, M. Steinbrueck, B. Fluhrer, T. Keim, M. Fischer, G. Langrock, P. Piluso, Z. Hozer, M. Kiselova, F. Belloni, M. Schyns, On the EU-Japan roadmap for experimental research on corium behavior, Annals of Nuclear Energy, Vol. 124, pp. 541-547 (2019).
      [2]K. Wang, N. Erkan, K. Okamoto, A new model for predicting the critical heat flux based on nucleation site density in downward-face boiling, J. Nuclear Science Technology, Vol.56, pp.1141-1156 (2019)
      [3]Q. Zhou, N. Erkan, K. Okamoto, Simultaneous measurement of temperature and flow distributions inside pendant water droplets evaporating in an upward air stream using temperature-sensitive particles, Nuclear Engineering Design, Vol. 345, pp.157-165 (2019)
      [4]B. Jo, K. Okamoto, N. Kasahara, Creep Buckling of 304 Stainless-Steel Tubes Subjected to External Pressure for Nuclear Power Plant Applications, Metals, Vol.9, No.536 (2019)
      [5]J. Aihara, S. Ueta, M. Honda, N. Mizuta, M. Goto, Y. Tachibana, K. Okamoto, Microstructures of ZrC coated kernels for fuel of Pu-burner high temperature gas-cooled reactor in Japan, Journal of Nuclear Materials, Vol. 522, pp.32-40 (2019)
      [6]K. Wang, N. Erkan, H. Gong, K. Okamoto. Effects of carbon steel surface oxidation on critical heat flux in downward-face pool boiling. Int. J. Heat. Mass. Transf. 136 (2019) 470?485.


      Year 2018

      Journal Publications

      [1] L. Wang, N. Erkan, H. Gong, K. Okamoto, Electron beam irradiation effect on critical heat flux in downward-facing flow boiling, International Journal of Heat and Mass Transfer, Vol. 120, pp. 300-304 (2018).
      [2] K. Silva, K. Okamoto, Discussion on probability of cesium-137 release exceeding 100 TBq as a part of the consideration of nuclear power plant probabilistic risk criteria for environmental protection, Reliability Engineering & System Safety, Vol. 180, pp. 88-93 (2018).
      [3] S. Ueda, B. Jo, M. Kondo, N. Erkan, T. Yajima, K. Okamoto, Initial relocation behavior of control rod materials in boiling water reactors studied via time-resolved visualization, Nuclear Engineering and Design, Vol. 333, pp. 99-114 (2018).
      [4] S, Ueta, J. Aihara, M. Goto, Y. Tachibana, K. Okamoto, Development of security and safety fuel for Pu-burner HTGR - Test and characterization for ZrC coating, Mechanical Engineering Journal, Vol. 5(5), pp. 18-00084-18-00084.
      [5] K. Wang, N. Erkan, H. Gong, L. Wang, K. Okamoto, Comparison of pool boiling CHF of a polished copper block and carbon steel block on a declined slope, Journal of Nuclear Science and Technology, Vol. 55(9), pp. 1065-1078 (2018).
      [6] B. Jo, N. Kasahara, K. Okamoto, Buckling of cylindrical stainless-steel tubes subjected to external pressure at extremely high temperatures, Engineering Failure Analysis, Vol. 92, pp. 61-70 (2018).
      [7] H. Gong, L. Wang, A.R. Khan, N. Erkan, K. Okamoto, Effects of downward-facing surface type and inclination on critical heat flux during pool boiling, Annals of Nuclear Energy, Vol. 113, pp. 344-352 (2018).
      [8] S. Ueda, H. Madokoro, M. Kondo, K. Okamoto, Numerical Analysis on Eutectic Melting of Boron Carbide Control Rod Materials, Transactions of JSCES, Paper No. 20182002 (2018).

      Conferences

      [1] Preliminary Research on the Oxidation Effect of the Carbon Steel Plate of Downward Facing Pool Boiling by Two-Dimensional Image,
      K. Wang, N. Erkan, K Okamoto,
      26th International Conference on Nuclear Engineering, London, England, July (2018).
      [2] Melting Simulation using a Particle Method with Angular Momentum Conservation,
      Masahiro Kondo, Shota Ueda, Koji Okamoto,
      25th International Conference on Nuclear Engineering, Shanghai, China, July (2018).
      [3] S. Ueda, K. Inagaki, M. Kondo, K. Okamoto, Investigation on Hydrodynamic Effect on Eutectic Melting, 71st Annual Meeting of the APS Division of Fluid Dynamics, November, Atlanta, Georgia (2018).


      Year 2017

      Journal Publications

      [1] H. Wei, N. Erkan, K. Okamoto, X. Gaus-Liu, A. Miassoedov, Improvement and evaluation of debris coolability analysis module in severe accident analysis code SAMPSON using LIVE experiment, Annals of Nuclear Energy, Vol. 100, pp. 65-72 (2017).
      [2] P. Chai, M. Kondo, N. Erkan, K. Okamoto, Numerical simulation of MCCI based on MPS method with different types of concrete, Annals of Nuclear Energy, Vol. 103, pp. 227-237 (2017).
      [3] H. Gong, A. Khan ,N. Erkan, L. Wang, K. Okamoto, Critical heat flux enhancement in downward-facing pool boiling with radiation induced surface activation effect, International Journal of Heat and Mass Transfer,vol. 109, pp. 93-102 (2017).
      [4] L. Wang, A. Khan, N. Erkan, H. Gong, K. Okamoto, Critical heat flux enhancement on a downward face using porus honeycomb plate in saturated flow boiling, International Journal of Heat and Mass Transfer, Vol. 109, pp. 454-461 (2017).
      [5] S. Ueda, H. Madokoro, B. Jo, M. Kondo, N. Erkan, K. Okamoto, Dynamic visualization of eutectic reaction between boron carbide and stainless steel, Journal of Nuclear Science and Technology, Vol. 54, pp. 81-88 (2017).
      [6] Q. Zhou, N. Erkan, K. Okamoto, Ex situ calibration technique for simultaneous velocity and temperature measurements inside water droplets using temperature-sensitive particles, Measurement Science and Technology, vol. 28 (2017).

      Conferences

      [1] Simultaneous Measurment of Temperature and Flow Distribution inside Pendant Water Droplets Evaporating in Upward Air Stream using Temperature-sensitive Particles,
      Quian Zhou, Nejdet Erkan, Koji Okamoto,
      17th International Topical Meeting on Nuclear Reactor Thermal Hydraulics, Xi'an, China, Sept.
      [2] Melting Simulation using a Particle Method with Angular Momentum Conservation,
      Masahiro Kondo, Shota Ueda, Koji Okamoto,
      25th International Conference on Nuclear Engineering, Shanghai, China, July


      Year 2016

      Journal Publications

      [1] S. Ueda, H. Madokoro, B. Jo, M.Kondo, N. Erkan and K. Okamoto, Time-resolved visualization technique for eutectic reaction between boron carbide and stainless steel at high temperatures, Mechanical Engineering Letters, Vol.2, (2016) 15-00056.
      [2] J. Cai, B. Jo, N. Erkan and K. Okamoto, Effect of non-condensable gas on thermal stratification and flow patterns in suppression pool, Nuclear Engineering and Design, vol. 300, pp. 117-126 (2016).
      [3] H. Wei, N. Erkan, K. Okamoto, Experimental investigation of the effect of control rod guide tubes on the breakup of a molten metal jet in the lower plenum of a boiling water reactor under isothermal conditions, Journal of Visualization, pp. 1-12 (2016).
      [4] P. Chai, M. Kondo, N. Erkan, K. Okamoto, Numerical simulation of 2D ablation profile in CCI-2 experiment by moving particle semi-implicit method, Nuclear Engineering and Design, Vol. 301, pp. 15-23 (2016).
      [5] N. Erkan, P. Chai, K. Okamoto, Natural convection in wake of molten matel moving with phase change of wax, Journal of Visualization, Vol. 19(2), pp. 171-174 (2016).
      [6] H. Lopez, N. Erkan, K. Okamoto, Reactor core isolation cooling system analysis of the Fukushima Daiichi Unit 2 accident with RELAP/ScdapSIM, Journal of Nuclear Science and Technology, Vol. 53, pp. 1899-1905 (2016).
      [7] D. Yamauchi, B. Jo, N. Erkan, S. Takahashi, W. Sagawa, K. Okamoto, Verification of thermal stratification characteristics using a scaled-down suppression pool of the Fukushima Daiichi nuclear power plants, Mechanical Engineering Letters, Vol.2, (2016) 1600092.
      [8] H. Lopez, N. Erkan, K. Okamoto, Twho-phase flow degradation on Fukushima-Daiichi Unit2 RCIC turbne performance, Journal of Nuclear Science and Technology, Vol.53, pp. 821-830 (2016).
      [9] B. Jo, N. Erkan, S. Takahashi, D. Song, W. Sagawa, K. Okamoto, Thermal stratification in a scaled-down suppression pool of the Fukushima Daiichi nuclear power plants, Nuclear Engineering and Design, Vol. 305, pp. 39-50 (2016).

      Conferences

      [1] Experimental Investigation Into Buckling Failure of Slender Metal Plates in Severe Accident Conditions,
      Byeongnam Jo, Wataru Sagawa, Koji Okamoto,
      2014 22nd International Conference on Nuclear Engineering, No. ICONE22-30829, pp. V001T03A024; 7 pages
      [2] Experimental Investigation Into Thermal Stratification by Direct Condensation in a Scaled Suppression Pool of Fukushima Daiichi Nuclear Power Plant,
      Byeongnam Jo, Shinji Takahashi, Daehun Song, Wataru Sagawa, Nejdet Erkan, Koji Okamoto,
      2014 22nd International Conference on Nuclear Engineering, Vol. 2A, No. ICONE22-30090, pp. V02AT09A010; 9 pages
      [3] Buckling Behaviors of Metallic Columns Under Compressive Load at Extremely High Temperatures,
      Byeongnam Jo, Wataru Sagawa, Koji Okamoto, ASME 2014 Pressure Vessels and Piping Conference,
      Vol. 3, No. PVP2-10-28683, pp. V003T03A103; 7 pages
      [4] SCDAP Model Improvement With QUENCH-06 Analysis, Hiroshi Madokoro, Koji Okamoto, Yuki Ishiwatari,
      2014 22nd International Conference on Nuclear Engineering, Vol. 5, No. ICONE22-30086, pp. V005T17A010; 8 pages
      [5] H. Madokoro, K. Okamoto, C. Allison, L. Siefken, J. Hohorst, and S. Hagen, "Assessment of RELAP/SCDAPSIM/MOD3.5 against the BWR core degradation experiment CORA-17," in The 10th International Topical Meeting on Nuclear Thermal-Hydraulics, Operation and Safety (NUTHOS-10), Okinawa, Japan, 2014, NUTHOS10-1243.
      [6] Q. Zhou, N. Erkan, K. Okamoto, Simultaneous velocity and temperature measurements inside droplet in hot air flow using TSPs & PIV,
      The 17th International Symposium on Flow Visualization, Gatlinburg, USA, 2016.


      Year 2015

      Journal Publications

      [1] H. Madokoro, N. Erkan, and K. Okamoto, "Assessment of the models in RELAP/SCDAPSIM with QUENCH-06 analysis." Journal of Nuclear Science and Technology, ahead-of-print, 2015
      [2] Maolong Liu, Nejdet Erkan, Yuki Ishiwatari, Koji Okamoto, Passive depressurization accident management strategy for boiling water reactors, Nuclear Engineering and Design, Vol. 284, pp.176-184 (2015)
      [3] M. Kondo, K. Yoneda, M. Furuya, & T. Nishi. An evaluation model to predict steam concentration in a BWR reactor building. Journal of Nuclear Science and Technology, (2015) doi:10.1080/00223131.2014.1000993.
      [4] Kazuya Shibata, Issei Masaie, Masahiro Kondo, Kohei Murotani, Seiichi Koshizuka, Improved pressure calculation for the moving particle semi-implicit method, Computational Particle Mechanics 2(1) (2015) 91-108.
      [5] Penghui Chai, Nejdet Erkan, Masahiro Kondo, Koji Okamoto and Hongyang Wei, Experimental research and numerical simulation of moving molten metal pool, Mechanical Engineering Letters 1 (2015) 15-00367.
      [6] Abdul R. Khan, Nejdet Erkan and Koji Okamoto, Heat transfer effect of an extended surface in downward-facing subcooled flow boiling, Nuclear Engineering and Design, vol 295, pp. 148-154 (2015)
      [7] N. Erkan, T. Kawakami, H. Madokoro, P. Chai, Y. Ishiwatari, K. Okamoto, Numerical simulation of droplet deposition onto a liquid film by VOF?MPS hybrid method. Journal of Visualization, Vol.18, (2015), pp.381-391
      [8] Y. Li, S. Someya, K. Okamoto, T. Inagaki, Y. Nishi, Visualization study of flow-excited acoustic resonance in closed tandem side branches using high time-resolved particle image velocimetry, J. Mechanical Sci. Technol. Vol.29, (2015) 989-999
      [9] D. Song, N. Erkan, B. Jo, K. Okamoto, Relationship between thermal stratification and flow patterns in steam-quenching suppression pool, Int. J. Heat Fluid Flow, Vol.56 (2015), 209-217
      [10] K. Silva, K. Okamoto, Y. Ishiwatari, S. Takahara, J. Promping, Consideration of decontamination model for severe accident consequence assessment, J. Nuclear Science Technology, Vol. 52, (2015) 1402-1416
      [11] K. Silva, K. Okamoto, Applicability of 100 TBq cesium 137 release into environment as a safety criterion for consequence assessment at reactor design approval stage, Journal of Nuclear Science and Technology, Vol.52, (2015) 1530-1539
      [12] H. Lopez, N. Erkan, K. Okamoto, Two-phase flow degradation on Fukushima-Daiichi Unit 2 RCIC turbine performance, Journal of Nuclear Science Technology, (2015) DOI: 10.1080/00223131.2015.1079507

      Conferences

      [1] Experimental Investigation Into Buckling Failure of Slender Metal Plates in Severe Accident Conditions,
      Byeongnam Jo, Wataru Sagawa, Koji Okamoto,
      2014 22nd International Conference on Nuclear Engineering, No. ICONE22-30829, pp. V001T03A024; 7 pages
      [2] Experimental Investigation Into Thermal Stratification by Direct Condensation in a Scaled Suppression Pool of Fukushima Daiichi Nuclear Power Plant,
      Byeongnam Jo, Shinji Takahashi, Daehun Song, Wataru Sagawa, Nejdet Erkan, Koji Okamoto,
      2014 22nd International Conference on Nuclear Engineering, Vol. 2A, No. ICONE22-30090, pp. V02AT09A010; 9 pages
      [3] Buckling Behaviors of Metallic Columns Under Compressive Load at Extremely High Temperatures,
      Byeongnam Jo, Wataru Sagawa, Koji Okamoto, ASME 2014 Pressure Vessels and Piping Conference,
      Vol. 3, No. PVP2-10-28683, pp. V003T03A103; 7 pages
      [4] SCDAP Model Improvement With QUENCH-06 Analysis, Hiroshi Madokoro, Koji Okamoto, Yuki Ishiwatari,
      2014 22nd International Conference on Nuclear Engineering, Vol. 5, No. ICONE22-30086, pp. V005T17A010; 8 pages
      [5] H. Madokoro, K. Okamoto, C. Allison, L. Siefken, J. Hohorst, and S. Hagen, "Assessment of RELAP/SCDAPSIM/MOD3.5 against the BWR core degradation experiment CORA-17," in The 10th International Topical Meeting on Nuclear Thermal-Hydraulics, Operation and Safety (NUTHOS-10), Okinawa, Japan, 2014, NUTHOS10-1243.
      [6] M. Kondo, K. Otsuka, T. Iwasaki, K. Yoshida, Stochastic numerical simulation to predict the dose-rate effect due to competition in stem cell pool, 15th International Congress of Radiation Research (ICRR 2015), 2015 May 25-29, Kyoto (poster)
      [7] Masahiro Kondo, Erkan Nejdet, Koji Okamoto, Steam Condensation Effect in Hydrogen Venting from a BWR Reactor Building, International Conference on Hydrogen Safety (ICHS 2015), 2015 October 19-21, Yokohama.
      [8] Shota Ueda, Hiroshi Madokoro, Byeongnam Jo, Masahiro Kondo, Koji Okamoto, "Visualization of B4C/SS Eutectic Reaction and Liquefaction for Code Development & Validation”, ASME 2015 Verification and Validation Symposium, VVS2015-8117, Nevada, U.S.A, (May 2015). [Extended Abstract]


      Year 2014

      Journal Publications

      [1] Measurement of buckling load for metallic plate columns in severe accident conditions,
      byeongnam Jo, Wataru Sagawa, Koji Okamoto, Nuclear Engineering and Design, Vol. 274, pp. 118-128 (2014)
      [2] Dimensional analysis of thermal stratification in a suppression pool, Daehun Song, Nejdet Erkan,
      Byeongnam Jo, Koji Okamoto,International Journal of Multiphase Flow, Vol. 66, pp. 92-100 (2014)
      [3] Full-field spreading velocity measurement inside droplets impinging on a dry slid surface,
      Nejdet Erkan, Koji Okamoto, Exp. Fluids, 55:1845 (2014)
      [4] Numerical simulation of droplet deposition on to a liquid film by VOF-MPS hybrid method,
      Journal of Visualization, Nejdet Erkan, Toshihiro Kawakami, Hiroshi Madokoro, Pengui Chai, Yuki Ishiwatari, Koji Okamoto, 1875-8975 (2014)
      [5] Study on flow-induced acoustic resonance in symmetrically located side-branches using dynamic PIV technique,
      Yanrong Li, Satoshi Someya, Koji Okamoto, Terumi Inagaki, Yasuyuki Nishi, Journal of Fluid Science and Technology 9(2), JFST0015-JFST0015 (2014)
      [6] M. Kondo, T. Arai, Y. Nishi, M. Furuya, T. Kanai, R. Morita, Y. Uchiyama, M. Satake, K. Shirakawa, Y. Nauchi, T. Koyama, K. Ishikawa and S. Suzuki, Early construction and operation of the highly contaminated water treatment system in Fukushima Daiichi nuclear power station (IV) - Assessment of hydrogen behavior in stored Cs adsorption vessel - , Journal of Nuclear Science and Technology 51 (2014) 916-929.
      [7] M. Liu, Y. Ishiwatari and K. Okamoto, Estimation of the depressurization process of Fukushima-Daiichi NPP unit 1 with SAMPSON, Nuclear Technology, Vol.186, pp. 216-228 (2014)

      Conferences

      [1] Experimental Investigation Into Buckling Failure of Slender Metal Plates in Severe Accident Conditions,
      Byeongnam Jo, Wataru Sagawa, Koji Okamoto,
      2014 22nd International Conference on Nuclear Engineering, No. ICONE22-30829, pp. V001T03A024; 7 pages
      [2] Experimental Investigation Into Thermal Stratification by Direct Condensation in a Scaled Suppression Pool of Fukushima Daiichi Nuclear Power Plant,
      Byeongnam Jo, Shinji Takahashi, Daehun Song, Wataru Sagawa, Nejdet Erkan, Koji Okamoto,
      2014 22nd International Conference on Nuclear Engineering, Vol. 2A, No. ICONE22-30090, pp. V02AT09A010; 9 pages
      [3] Buckling Behaviors of Metallic Columns Under Compressive Load at Extremely High Temperatures,
      Byeongnam Jo, Wataru Sagawa, Koji Okamoto, ASME 2014 Pressure Vessels and Piping Conference,
      Vol. 3, No. PVP2-10-28683, pp. V003T03A103; 7 pages
      [4] SCDAP Model Improvement With QUENCH-06 Analysis, Hiroshi Madokoro, Koji Okamoto, Yuki Ishiwatari,
      2014 22nd International Conference on Nuclear Engineering, Vol. 5, No. ICONE22-30086, pp. V005T17A010; 8 pages
      [5] H. Madokoro, K. Okamoto, C. Allison, L. Siefken, J. Hohorst, and S. Hagen, "Assessment of RELAP/SCDAPSIM/MOD3.5 against the BWR core degradation experiment CORA-17," in The 10th International Topical Meeting on Nuclear Thermal-Hydraulics, Operation and Safety (NUTHOS-10), Okinawa, Japan, 2014, NUTHOS10-1243.
      [6] Masahiro Kondo, Kimitoshi Yoneda and Yoshihisa Nishi, Numerical Study of Hydrogen Venting froma a Reactor Building Affected by the External Wind, The 9th Korea-Japan Symposium on Nuclear Thermal Hydraulics and Safety (NTHAS9), 2014 November 16-19, Buyeo.


      Year 2013

      Journal Publications

      [1] M. Liu, Y. Ishiwatari, "Unsteady numerical simulations of single-phase turbulent mixing in tight lattice geometries," Nucl. Eng. Des., 256, 28-37 (2013)
      [2] M. Liu, Y. Ishiwatari, K. Okamoto, “Estimation of the depressurization process of Fukushima Daiichi NPP Unit 1”, 混相流(日本混相流学会誌), 27[2] (2013)
      [3] K. Kawahara, Y. Ishiwatari, M. Liu, “Sensitivity analysis regarding alternative water injection in long-term station blackout of BWR,”
      J. Nucl. Sci. Tech., 50[2], 201?211 (2013) [4] Y. Li, S. Someya, T. Koso, S. Aramaki, K. Okamoto, “Characterization of periodic flow structure in a small-scale feedback fluid oscillator under low-Reynolds-number water flow,” Flow Measurement and Instrumentation, Vol.33, (2013) 179-187

      Conferences

      [1] Improvement of SAMPSON Code for BWR Severe Accident Analysis, Maolong Liu, Yuki Ishiwatari,
      Koji Okamoto, 2013 21st International Conference on Nuclear Engineering, Vol. 6, No. ICONE21-16719, pp. V006T15A021; 9 pages


      Year 2012

      Journal Publications

      [1] M. Liu, Y. Ishiwatari, K. Okamoto, “Estimation of the Depressurization Process of Fukushima Dai-ichi NPP Unit 1 with SAMPSON”, Nuclear Technology (International Meeting on Severe Accident Assessment and Management: Lessons Learned from Fukushima Dai-ichi, Embedded topical meeting of 2012 ANS Winter Meeting and Nuclear Technology Expo
      [2] T. Fujiwara, T. Saito, Y. Muroya, H. Sawahata, Y. Yamashita, S. Nagasaki, K. Okamoto, H. Takahashi, M. Uesaka, Y. Katsumura and S. Tanaka, “Isotopic ratio and vertical distribution of radionuclides in soil affected by the accident of Fukushima Dai-ichi nuclear power plants,” J. Environmental Radioactivity. Vol.113 (2012) 37-44.
      [3] 岡本孝司, 「全電源喪失について」, 日本原子力学会誌, Vol.54, No.1, pp27-31 (2012).


      Year 2011

      Journal Publications

      [1] Lifetime-based phosphor thermometry of an optical engine using a high-speed CMOS camera,
      Someya S.*, Uchida M., Tominaga K., Terunuma H.,Li Y., Okamoto K.,
      Int.J. Heat and Mass Transfer, Vol.54(17-18), pp.3927-3932, 2011
      [2] A Fractal-based 2D Expansion Method for Multi-scale Volume Data Visualization,
      Fujiwara T., Iwamaru M., Tange M., Someya S., Okamoto K.,
      Journal of Visualization, Vol.14, No.2, pp.171-190(2011)
      [3] An entrained droplet by an unexpanded gas jet into water,
      Someya S.**, Uchida M., Li Y., Ohshima H., Okamoto K.,
      Journal of Visualization, DOI: 10.1007/s12650-011-0089-7 (2011)
      [4] 蛍光体を用いたエンジン筒内ガス温度速度同時計測，
      染矢聡*，内田光則，大倉康裕，佐藤義久，岡本孝司，
      Trans. JSME B, Vol.xx(xx), pp.xx-xx, 2011 (in print)
      [5] T. Fujiwara, M. Iwamaru, M. Tange, S. Someya and K. Okamoto, “A Fractal-based 2D Expansion Method for Multi-scale Volume Data Visualization,” Journal of Visualization, Vol.14, No.2, pp.171-190
      [6] S. Someya, Y. Li, K. Ishii K. Okamoto, “Combined Two-Dimensional Velocity and Temperature Measurements of Natural Convection using a High-speed Camera and Temperature Sensitive Particles,”, Experiments in Fluids, (2011) Vol.50(1), pp.65-73
      [7]二ノ方壽, 岡本孝司, 「福島第一原子力発電所事故から学ぶ」日本原子力学会誌, Vol.53, No.1, pp540-545 (2011).

      Conferences

      [1] Visualization Study on Flow-induced Acoustic Resonance in Piping System with Closed Coaxial
      Sidebranches, Yanrong Li, Satoshi Someya, Koji Okamoto,
      Young Engineers and Scientists Symposium 2011“Alternative Energies ? A Global Perspective”, Paper No.8, Texas A&M University, U.S.A., 1/10-12 (2011)
      [2] Experimental Investigation of Flow-induced Vibration Interference between Two Tandem Circular Cylinders,
      Shusaku Hotta, Qian Xu, Satoshi Someya, Koji Okamoto,
      Young Engineers and Scientists Symposium 2011“Alternative Energies ? A Global Perspective”, Paper No.9, Texas A&M University, U.S.A., 1/10-12 (2011)
      [4] Acceleration of Recursive Cross-Correlation PIV using Multiple GPUs,
      Shuhei Tarashima, Satoshi Someya, Koji Okamoto,
      The 8th ASME-JSME Thermal Engineering Joint Conference (AJTEC2011), ?Paper No.AJTEC2011-44442, Hawai, U.S.A., 3/13-17(14), (2011)

      Invited/Keynote Talks (2009〜)

      [1] Outline of HTGR, its advantage and merit,
      K. Okamoto, The 2nd UAE-Japan Multipurpose HTGR Form, Feb. 28, 2016, (Sharjar, UAE)
      [2] Numerical Simulation Developments and V&V for Severe Accident Analysis,
      K. Okamoto, Workshop of Nuclear Power Software Development, December 22, 2015, (Beijing, China)
      [3] CFD Challenge on Severe Accident Analysis,
      K. Okamoto, International Symposium on Severe Accidents Simulation and Experiments for Nuclear Power Plants, December 2-4, 2015, (Zhuhai, China)
      [4] Safety management to promote a strong safety culture and achieve good safety,
      K. Okamoto, Northeast Asia Nuclear Safety Cooperation Conference (The 3rd TRM+) Oct. 22-23, 2015, (Seoul, Korea)
      [5] Collaboration Research between ICL and UT,
      K. Okamoto, UK-Japan Nuclear Research Collaboration Workshop, Sept. 10, 2015, London, UK.
      [6] Challenge on Severe Accident Simulation,
      K. Okamoto, Workshop of Nuclear Power Software Development, December 22, 2015, (Beijing, China)
      [7] Numerical Simulation Developments and V&V for Severe Accident Analysis,
      K. Okamoto, 原子力学会秋の大会, 計算科学技術部会企画セッション, Sept. 9, 2015, (静岡、日本)
      [8] Beyond design basis accidents,
      K. Okamoto, 23th Int. Conf. on Nuclear Engineering, May 19, 2015 (Makuhari, Japan)
      [9] Severe Accident analysis and PIRT development for Fukushima-Daiichi NPP,
      K. Okamoto, 1st Sino-German Symposium on Fundamentals of Advanced Nuclear Safety Technology, Mar.10, 2015 (Shanghai, China)
      [10] Nuclear Safety Activity for East Asia,
      K. Okamoto, The 3rd East-Asian Nuclear Forum, Apr. 30, 2015 (Seoul, Korea)
      [11] 原子力安全確保の規格基準体系の基本的考え方,
      K. Okamoto, 日本原子力学会秋の大会、標準委員会企画セッション、Sept.9, 2014, 京都
      [12] Post-Fukushima Research Activities for Nuclear Safety,
      K. Okamoto, International Nuclear Science and Technology Conference, August 30, 2014 (Bangkok, Thailand)
      [13] Post-Fukushima Code and Standard,
      K. Okamoto, 22th Int. Conf. on Nuclear Engineering, July 8, 2014 (Prague, Chez)
      [14] Lessons Learned from Fukushima-Daiichi NPP Accident,
      K. Okamoto, Topical meeting on International Nuclear Law Symposium, Nov.6-7, 2013, (Tokyo, Japan)
      [15] Decommissioning of NPP,
      K. Okamoto, EDENS Workshop on safety concerns and decommissioning preparedness, Mar. 12 2013, (Seoul, Korea)

      総説・解説(Commentaries)

      [1] 原子力規制の考え方,
      岡本孝司,
      エネルギーレビュー, vol. 35, No. 6, (2015)
      [2] 格納容器におけるシビアアクシデント,
      岡本孝司,
      エネルギーレビュー, Vol. 35, No. 9, (2015)
      [3] 福島第一発電所のリスク,
      岡本孝司,
      エネルギーレビュー, Vol. 34, No. 2, (2014)
      [4] これからの日本　どうするエネルギー―天動説と地動説,
      岡本孝司,
      エネルギーレビュー, Vol. 34, No. 5, (2014)
      [5] 超安全な原子炉は可能か―超安全炉の考え方,
      岡本孝司,
      エネルギーレビュー, Vol. 34, No. 6, (2014)
      [6] 福島第一はコントロールされている,
      岡本孝司,
      エネルギーレビュー, Vol. 33, No. 12, (2014)
      [7] 原子力に関する可視化研究,
      染矢聡*, 岡本孝司, 日本原子力学会熱流動部会
      ニュースレター, Vol. 75, (2011)