研究领域或方向
电弧焊，激光焊接，激光电弧复合焊接，激光增材制造，基于CFD的激光加工过程"传热-冶金-力学"行为数字孪生研究。
工作经历
1. 2018年8月-至今304永利集团官网入口，教授
2. 1983年-2017年，韩国科学技术院机械工程系，教授
教育经历
1.1978-10至1983-03, TU Braunschweig, Mechanical Engineering, 博士
2. 1975-03至1977-02, KAIST, Mechanical Engineering, 硕士
3. 1971-03至1975-02, Seoul National University, Mechanical Engineering, 学士
科研项目
(1) 韩国科学技术院, 自然科学项目, 基于CFD数值模拟激光-金属颗粒相互作用的金属选区激光熔覆工艺设计研究, 项目负责人
(2) 芬兰国家技术创新局, “芬兰杰出教授计划”项目, 基于数字材料工程和质量与热流建模的材料连接优化技术研究, 项目负责人
(3) 韩国国家基金会, 重点项目, 面向机械设计的基于CFD的焊接变形控制可视化研究, 项目负责人
(4) 韩国国家基金会, 自然科学项目，高亮度激光-电弧复合焊接的三维模拟及可视化研究, 项目负责人
(5) 韩国机械材料研究所, 自然科学项目超精密/超高速激光加工系统关键部件开发技术研究, 项目负责人
(6) 现代汽车有限公司,自然科学项目,金属-聚合物异质激光焊接接头气孔缺陷控制策略研究,项目负责人
(7) Seojin有限公司,自然科学项目,高强钢/铝合金异质接头高效搅拌摩擦焊工艺研究,项目负责人
(8) 弘益大学,自然科学项目,半导体显示面板的热处理系统原创技术开发研究, 项目负责人
(9) 海钢有限公司,自然科学项目,用于运输含H2S油/气体的X80 SAW钢管的制造及应用技术开发,项目负责人
(10) 浦项制铁公司,自然科学项目,多电弧埋弧自动焊(SAW)熔池热传导行为分析,项目负责人
(11) 浦项制铁公司,自然科学项目,开发基于逆向电算工程的数值模拟技术,项目负责人
(12) 浦项技术研究所,自然科学项目,开发未来城市环保设计与制造技术,项目负责人
(13) 大宇造船海洋株式会社,自然科学项目,开发利用反函数解法矫正薄板焊接变形的自动化算法,项目负责人
学术成果
(1)目前累计发表186篇SCI论文；93篇韩国国内期刊的研究论文；
(2)在国际会议上进行过148次演讲（16次应邀，9次主旨演讲，7次全体会议）；在韩国国内会议上发言128次（1次邀请）；
(3)个人专著1部，参编专著2部；
(4)在韩国注册了26项专利。
学术奖励
(1) Humboldt Research Award, Humboldt Foundation, , 国际学术奖, 2016
(2) Yoshiaki Arata Award, IIW, 国际学术奖, 2014
(3) Houdremont Lecture Award, IIW, 国际学术奖, 2014
(4) FiDiPro (Finland Distinguished Professor Program) Professor, Finland , 国际学术奖, 2014
(5) IIW Fellow Award, International Institute of Welding , 国际学术奖, 2010
(6) KWJS President, Korea Welding & Joining Society, 其他, 2007
(7) A.F. Davis Silver Medal Award, American Welding Society , 国际学术奖, 2006
(8) AWS Fellow, America Welding Society，国际学术奖, 2004
(9) Charles H. Jennings Memorial Award, American welding society, 国际学术奖, 2003
学术论文 (从2010-至今)
1. 发表国际期刊论文
[77] L.J. Zhang, R.Y. Ma*, Y.B. Zhang, Q. Guo, C.H. Wang, J.X. Zhang, S.-J. Na. Investigation on dissimilar laser beam welding of molybdenum to zirconium via pure titanium interlayer [J]. Optics and Laser Technology, 2020. (Accepted)
[76] J. Ning, L.J. Zhang*, L.L. Zhang, J. Long, X.Q. Yin, J.X. Zhang, S.-J. Na. Effects of power modulation on behaviours of molten pool and keyhole during laser-arc hybrid welding of pure copper [J]. Materials & Design, 2020. (Accepted)
[75] L.J. Zhang, Q. Guo*, Y.B. Zhang, R.Y. Ma, C.H. Wang, J.X. Zhang, S.-J. Na. Microstructure and Performance of Laser-Welded GH3128/Mo Dissimilar Joints [J], Journal of Materials Engineering and Performance, 2020, 29:1792-1809.
[74] J. Long, L.J. Zhang*, L.L. Zhang, X.Q. Yin, J.X. Zhang, S.-J. Na. Towards better understanding of hyperbaric fiber laser spot welding of metallic material [J], Journal of Manufacturing Processes, 2020, 56:372-381.
[73] J. Long, L.J. Zhang*, L.L. Zhang, X. Wang, G.F. Zhang, J.X. Zhang, S.-J. Na, Effects of minor Zr addition on the microstructure and mechanical properties of laser welded joint of Al/SiCp metal-matrix composite [J], Journal of Manufacturing Processes, 2020, 49:373-384.
[72] L.J. Zhang*, J.Y. Pei*, L.L. Zhang, J. Long, J. Ning, G.F. Zhang, S.G. Li, G. An, J.X. Zhang, S.-J. Na, Laser seal welding of end plug to thin-walled nanostructured high-strength molybdenum alloy cladding with a Zirconium interlayer [J], Journal of Materials Processing Technology, 2019, 267:338-347
[71] S. Li, L.J. Zhang*, J. Ning, X. Wang, G.F. Zhang, J.X. Zhang, S.-J. Na, B. Fatemeh. Comparative study on the microstructures and properties of wire+arc additively manufactured 5356 aluminium alloy with argon and nitrogen as the shielding gas [J], Additive Manufacturing, 2020, 34:101206.
[70] J. Ning, L.J. Zhang*, X.Q. Yin, J.X. Zhang, S.-J. Na, Mechanism study on the effects of power modulation on energy coupling efficiency in infrared laser welding of high-reflectivity materials [J], Materials & Design, 2019,178:107871.
[69] L.L. Zhang, L.J. Zhang*, J. Long, X. Sun, J.X. Zhang, S.-J. Na, Enhanced mechanical performance of fusion zone in laser beam molybdenum alloy due to solid carburizing [J], Materials & Design, 2019, 181:107957.
[68] L.L. Zhang, L.J. Zhang*, J. Long, J. Ning, J.X. Zhang, S-J. Na. Effects of titanium on grain boundary strength in molybdenum laser weld bead and formation and strengthening mechanisms of brazing layer [J]. Materials & Design, 2019, 169:107681.
[67] L.J. Zhang, C.H. Wang*, Y.B. Zhang, Q. Guo, R.Y. Ma, J.X. Zhang, S.-J. Na, The mechanical properties and interface bonding mechanism of Molybdenum/SUS304L by laser beam welding with nickel interlayer [J], Materials &Design, 2019,182:108002.
[66] J.H. Wen, L.J. Zhang*, J. Ning*, F. Xue, X.W. Lei, J.X. Zhang, S.-J. Na. Laser additively manufactured intensive dual-phase steels and their microstructures, properties and corrosion resistance [J], Materials & Design, 2020, 192:108710.
[65] L.J. Zhang, G.F. Lu*, J. Ning, Q. Zhu, J.X. Zhang, S.-J. Na, Effects of minor Zr addition on the microstructure and mechanical properties of laser welded dissimilar joint of titanium and molybdenum [J], Materials Science & Engineering A, 2019, 742:788-797.
[64] L.J. Zhang*, J.Z. Liu*, J.Y. Pei, J. Ning, L.L. Zhang, J. Long, G.F. Zhang, J.X. Zhang, S.-J. Na, Effects of power modulation, multipass remelting and Zr addition upon porosity defects in laser seal welding of end plug to thin-walled molybdenum alloy [J], Journal of Manufacturing Processes, 2019, 41:197-207.
[63] J. Long, L.J. Zhang*, L.L. Zhang, J. Ning, Y.X. Yin, J.X. Zhang, S.-J. Na, Fiber laser spot welding of molybdenum alloy in a hyperbaric environment [J], Optic express, 2019, 28:7843-7857.
[62] T.-H. Na, S.-J. Na, Y.-W. Park*, A Study on Characteristics of End Plug Resistance Welding Process in Nuclear Fuel Rods by Experiment and Numerical Simulation [J], International Journal of Advanced Manufacturing Technology, 2018, 98:2241-2251.
[61] T.-H.Na, S.-J.Na*, Quality Monitoring of End Plug Resistance Weldment for Nuclear Fuel Rods by Electrode Displacement [J], International Journal of Advanced Manufacturing Technology, 99:2509-2522, 2018.
[60] C.X. Zhu, J. Cheon, X.H.Tang*, S.-J.Na*, F.G. Lu, H.C. Cui. Molten pool behaviors and their influences on welding defects in narrow gap GMAW of 5083 Al-alloy [J], International Journal of Heat and Mass Transfer, 2018, 126:12061221.
[59] C.X. Zhu, J. Cheon, S.-J.Na*, F.G.Lu, H.C.Cui, X.H.Tang. Effect of swing arc on molten pool behaviors in narrow-gap GMAW of 5083 Al-alloy [J], Journal of Materials Processing Technology, 2018, 259:243258.
[58] Y.-X.Zhang, D.-Y.You, X.-D.Gao*, S.-J.Na. Automatic gap tracking during high power laser welding based on particle filtering method compensated by BP neural network [J], Int. J. of Advanced Manufacturing Technology, 2018, 96, 685696.
[57] S.Muhammad, S.-W.Han, S.-J.Na*, A. Gumenyuk, M. Rethmeier. A study on the role of recondensation flux in high power laser welding by CFD simulations [J], Journal of Laser Applications, 2018, 30:012013.
[56] H.-P.Cheon, J.-Y.Yoon, C.-H.Kim, S.-J.Na*. A study on transient flow characteristic in friction stir welding with real-time interface tracking by direct surface calculation [J], Journal of Materials Processing Technology, 2018, 255:621634.
[55] D.-W.Cho*, D.V.Kiran, S.-J.Na. Analysis of molten pool behavior by flux-wall guided metal transfer in low current submerged arc welding [J], International Journal of Heat and Mass Transfer, 2017, 110:104112.
[54] S.-D.Kim, J.-Y.Yoon, S.-J.Na*. A study on characteristics of FSW tool shapes based on CFD analysis [J], Welding in the World, 2017, 61:915926.
[53] W.J.Ge, S.W.Han, Y.C. Fang, J.Cheon, S.-J.Na*. Mechanism of surface morphology in electron beam melting of Ti6Al4V based on computational flow patterns [J], Journal of Applied Surface Science, 2017, 419:150158.
[52] H.-P.Cheon, S.-J.Na*. Prediction of welding residual stress with real-time phase transformation by CFD thermal analysis [J], Int. Journal of Mechanical Sciences, 2017, 131:037051
[51] Y.-X. Zhang, S.-W. Han, J. Cheon, S.-J. Na*, X.-D. Gao. Effect of joint gap on bead formation in laser butt welding of stainless steel [J], Journal of Materials Processing Technology, 2017, 249:274284.
[50] J. Pocorni, S.-W. Han, J. Cheon, S.-J. Na, A. Kaplan*, H.-S. Bang. Numerical simulation of laser ablation driven melt waves [J], Journal of Manufacturing Processes, 2017, 30:303312.
[49] S. Muhammad, M. Karhu, S.-J. Na*, S.-W. Han, V. Kujanpaa. Effect of leading and trailing torch configuration on mixing and fluid behavior of laser-GMA hybrid welding [J], Journal of Laser Applications, 2017, 29:042009.
[48] L-J. Zhang, S-J. Na*, J-X. Zhang. Using Arc Pressure to Investigate the Effects of Energy Source Distance on Arc Plasma Behavior in Pulsed Nd:YAG Laser/Tungsten Inert Gas (TIG) Arc Hybrid Welding [J], Lasers in Engineering, 2016, 33:279292.  
[47] H.-P. Cheon, D.V. Kiran, S.-J. Na*. Thermal metallurgical analysis of GMA welded AH36 steel using CFD-FEM framework [J], Journal of Materials and Design, 2016, 91:230241.
[46] S.-W. Han, J.-S. Ahn, S.-J. Na*. A study on ray tracing method for CFD simulations of laser keyhole welding: Progressive Search Method [J], Welding in the World, 2016, 60:247258.
[45] D.V.Kiran, J.Cheon, A.Nabeel, H.Chung, S.-J.Na*. CFD simulations of GMA welding of horizontal fillet joints based on coordinate rotation of arc models [J], Journal of Materials Processing Technology, 2016, 86:14531474.
[44] L. Wu, H.-P. Cheon, D.V. Kiran, S.-J. Na*. CFD simulations of GMA welding of horizontal fillet joints based on coordinate rotation of arc models [J], Journal of Materials Processing Technology, 2016, 231:221238.
[43] H.-P. Cheon, D.V. Kiran, S.-J. Na*. CFD based visualization of the finger shaped evolution in the gas metal arc welding process [J], International Journal of Heat and Mass Transfer, 2016, 99:001014.  
[42] D.-J. Jung, H.-P. Cheon, S.-J. Na*. Effect of surface pre-oxidation on laser assisted joining of acrylonitrile butadiene styrene (ABS) and zinc-coated steel [J], Journal of Materials and Design, 2016, 99:001009.
[41] D.-W. Cho*, D.V. Kiran, S.-J. Na. Influence of simulation methods of temperature distribution on thermal and metallurgical characteristics in GMA welding [J], Journal of Materials and Design, 2016, 108:183194.
[40] T.-H. Na, S.-J. Na*, M.-H. Ko, D.-S. Hwang. Algorithm development for quality monitoring on end plug resistance weldment of nuclear fuel rods [J], International Journal of Advanced Manufacturing Technology, 2016, 85:991-1006.
[39] L-J. Zhang, S-J. Na*, J-X. Zhang. Using Arc Pressure to Investigate the Effects of Energy Source Distance on Arc Plasma Behavior in Pulsed Nd:YAG Laser/Tungsten Inert Gas (TIG) Arc Hybrid Welding [J], Lasers in Engineering, 2016, 33:279-292.
[38] D.V.Kiran, D.-W.Cho, H.-K.Lee, C.-Y.Kang, S.-J.Na*.A study on the quality of two wire tandem submerged arc welds under iso-heat input conditions [J], International Journal of Advanced Manufacturing Technology, 2015, 78 (1):53-62.
[37] Y.-T. Cho, S.-J. Na*. Numerical analysis of plasma in CO2 laser and arc hybrid welding [J], International Journal of Precision Engineering and Manufacturing, 2015, 16 (4):787-795.
[36] M. Sohail, S.-W. Han, S.-J. Na*, A.Gumenyuk, M.Rethmeier. Numerical investigation of energy input characteristics for high power fiber laser welding at different positions [J], International Journal of Advanced Manufacturing Technology, 2015, 80:931-946.
[35] D.V.Kiran, D.-W.Cho, W.H.Song, S.-J.Na*. Arc interaction and molten pool behavior in the three wire submerged arc welding process [J], International Journal of Heat and Mass Transfer, 2015, 87:327-340.
[34] D.-W.Cho, S.-J.Na*. Molten pool behaviors for second pass V-groove GMAW [J], International Journal of Heat and Mass Transfer, 2015, 88:945-956.
[33] J.Powell*, T.Ilar, J.Frostevarg, M.J.Torkamany, S.-J.Na, D.Petring, L.Zhang, A.F.H.Kaplan. Weld root instabilities in fiver laser welding [J], Journal of Laser Applications, 2015, 27:S29008/1-S29008/5.
[32] D.-W.Cho, D.V.Kiran, S.-J.Na*. Analysis of flux consumption for tandem submerged arc welding process under iso-heat input conditions [J], Research Supplement of Welding Journal, 2015, 94:396S-401S.
[31] D.-W.Cho, W.-I.Cho, S.-J.Na*. Modeling and simulation of arc, laser and hybrid welding process [J], Journal of Manufacturing Processes, 2014, 16:26-55.
[30] D.V.Kiran, D.-W.Cho, W.H.Song, S.-J.Na*. Arc behavior in two wire tandem submerged arc welding process [J], Journal of Materials Processing technology, 2014 , 214:1546-1556.
[29] L.-J.Zhang, J.-X.Zhang, A.Gumenyuk, M.Rethmeier, S.-J.Na*. Numerical simulation of full penetration laser welding of thick steel plate with high power high brightness laser [J], Journal of Materials Processing technology, 2014, 214:1710-1720.
[28] M.Sohail, S.-W.Han, S.-J.Na*, A.Gumenyuk, M.Rethmeier. Characteristics of weld pool behavior in laser welding with various power inputs [J], Welding in the World, 2014, 58:269-277.
[27] D.-W.Cho, D.V.Kiran, W.H.Song, S.-J.Na*. Molten pool behavior in tandem submerged arc welding process [J], Journal of Materials Processing technology, 2014, 214:2233-2247.
[26] J.Cheon, S.-J.Na*.Relation of joint strength and polymer molecular structure in laser assisted metal and polymer joining [J], Science and Technology of Welding and Joining, 2014,19(8):631-639.
[25] Q.Nadeem, S.-J.Na*. An approach to form the dome shape by 3D laser forming [J], Chinese Optics Letters, 2013, 11(2):021402/1- 021402/4.
[24] D.-W.Cho, S.-J.Na*, M.-H.Cho, J.-S.Lee. A study on V-groove GMAW for various welding positions [J], Journal of Materials Processing technology, 2013, 213:1640-1652.
[23] W.-J.Seong, Y.-C.Jeon, S.-J.Na*. Ship-hull plate forming of saddle shape by geometrical approach [J], Journal of Materials Processing technology, 2013, 213:1885-1893.
[22] J.-S.Ahn, S.-J.Na*. Three-dimensional thermal simulation of nanosecond laser ablation for semitransparent material [J], Applied Surface Science, 2013, 283:115-127.
[21] D.-W.Cho, W.-H.Song, M.-H.Cho, S.-J.Na*. Analysis of submerged arc welding process by three-dimensional computational fluid dynamics simulations [J], Journal of Materials Processing technology, 2013, 213:2278-2291.
[20] D.-W. Cho, S.-J. Na*, M.-H. Cho, J.-S. Lee. Simulations of Weld Pool Dynamics in V-groove GTA and GMA Welding [J], Welding in the World, 2013, 57: 223-233.
[19] S-W. Han, W-I. Cho, S-J. Na*, C-H. Kim. Influence of Driving Forces on Weld Pool Dynamics in GTA and Laser Welding [J], Welding in the World, 2013, 57: 257-264.
[18] D.-W. Cho, S.-H. Lee, S.-J. Na*. Characterization of welding arc and weld pool formation in vacuum gas hollow tungsten arc welding [J], Journal of Materials Processing technology, 2013, 213: 143-152.
[17] J.-W. Noh, J.-H. Lee, S.-J. Na*. Fabrication of a random convex-lens-shaped microstructure using a laser ablation [J], Current Applied Physics, 2012, 12(No.5): 1307-1312.
[16] J.-W. Noh, I.-H. Cho, S.-W. Lee, S.-J. Na*, J.-H. Lee. Fabrication of microgrooves on a curved surface by the confocal measurement system using pulse and continuous laser [J], Review of Scientific Instruments, 2012, 83: 033106/1-033106/5
[15] R.-H. Kim, G.-D. Choi, C.-H. Kim, D.-W. Cho, S.-J. Na*. Arc characteristics in pulse-GMA welding with acute groove angles [J], Welding Journal-Including Welding Research Supplement, 2012, 91(No.4): 101/s - 105/s.
[14] W.-I. Cho, S.-J. Na*, C. Thomy, F. Vollertsen. Numerical simulation of molten pool dynamics in high power disk laser welding [J], Journal of Materials Processing Technology, 2012, 212: 262-275.
[13] Q. Nadeem, W.-J. Seong, S.-J. Na*. Process designing for laser forming of circular sheet metal [J], Chinese Optics Letters, 2012, 10(2): 021405/1-021405/3.
[12] Q. Nadeem, S.-J. Na*. Deformation behavior of laser bending of circular sheet metal [J], Chinese Optics Letters, 2011, 9(5): 051402/1-051402/5.
[11] Y.-T. Cho, W.-I. Cho, S.-J. Na*. Numerical analysis of hybrid plasma generated by Nd: YAG laser and gas tungsten arc [J], Optics and Laser Technology, 2011, 43: 711-720.
[10] J.-W. Noh, J.-H. Lee, S.-Y. Lee, S.-J. Na*. Fabrication of random micro-spikes on mold metal by ultrashort laser ablation for hydrophilic surface [J], Japanese Journal of Applied Physics, 2010, 49: 106503/1-106503/7.
[9] J.-W. Noh, J.-H. Lee, S.-J. Na*, H.-E. Lim, D.-H. Jung. Fabrication of hierarchically micro- and nano-structured mold surfaces using laser ablation for mass production of superhydrophobic surfaces [J], Japanese Journal of Applied Physics, 2010, 49(10): 106502/1-106502/6.
[8] S.-J. Na*, W.-I. Cho, D.-W. Cho. Simulations of weld pool dynamics and its visualization [J], Transaction of JWRI, 2010, 39(2): 34-36.
[7] D.-W. Cho, S.-J. Na*, M.-H. Cho, J.-S. Lee. Numerical simulation of molten pool flow for various welding parameters in V-groove GMA pipe welding [J], Transaction of JWRI, 2010, 39(2): 9-10.
[6] W.-J. Seong, Junsn Ahn, S.-J. Na*, M.-S. Han, Y.-C. Jeon. Geometrical approach for flame forming of single curved ship hull plate [J], Journal of Materials Processing Technology, 2010, 210: 1811-1820.
[5] J.-W. Noh, J. Suh, S.-J. Na*. Fabrication of micro grooves on roll surfaces using a scanner and a telecentric lens [J], Japanese Journal of Applied Physics, 2010, 49 (5issue2): P.05EC01.1-05EC01.6.
[4] K.-W. Park, S.-J. Na*. Effect of particle size on the UV pulsed-laser scribing in CFD-based simulations [J], Journal of Applied Physics, 2010, 107(11): 113112.1-113112.7.
[3] D. Y. Seong, C. G. Jung, D. Y. Yang*, J. Ahn, S.-J. Na, W.J. Chung, J. H. Kim. Analysis of core shear stress in welded deformable sandwich plates to prevent de-bonding failure during U-bending [J], Journal of Materials Processing Technology, 2010, 210: 1171-1179.
[2] W.-I. Cho, S.-J. Na*, M.-H. Cho, J.-S. Lee. Numerical study of alloying element distribution in CO2 laser-GMA hybrid welding [J], Computational Materials Science, 2010, 49: 792-800.
[1] K.-W. Park, S.-J. Na*. Theoretical investigations on multiple-reflection and Rayleigh absorption–emission–scattering effects in laser drilling [J], Applied Surface Science, 2010, 256: 2392-2399.
2. 在国际会议上的受邀、主旨和全体会议演讲
[23] S.-J.Na, “Metallurgical and Mechanical Characterization of Welded Structures based on CFD Process Simulations”, Plenary speech, 2019 AWS Professional Program, Chicago, USA, 2019, November.
[22] S.-J.Na, “Metallurgical and Mechanical Characterization of Welded Structures based on CFD Process Simulations”, Keynote speech, Int. Workshop on Intelligentized Welding Manufacturing, Shanghai, China, 2019, November
[21] S.-J.Na, “Participatory design of welding processes using CFD-based coupled simulations of thermal, metallurgical and mechanical behavior”, Invited speech, International Seminar on Repair Standard and Remanufacturing Technology of Special Pressure Equipment in Power Station, Suzhou, China, 2019, May
[20] Jason Cheon, S.-W.Han, W.-J.Ge, S.-J.Na, “CFD welding simulation and its application”, Invited speech, International Conference of the 70th Annual Assembly of the International Institute of Welding, Shanghai, China, 2017, June
[19] S.-J.Na, “Virtual welding and additive manufacturing based on CFD simulations”, Invited speech, Int. Workshop on Intelligentized Welding Manufacturing, Shanghai, China, 2017, June
[18] S.-J.Na, “Modeling and simulation issues in CFD simulations of keyhole laser welding”, Invited speech, 27th International SAOT Workshop on Modeling Laser Material Processing, Erlangen, Germany, 2016, December
[17] S.-J.Na, J.Cheon, S.-W.Han, S.-D.Kim, D.-W.Cho, Y.-C.Fang, W.-J.Ge, “Some issues in modeling for CFD simulations of welding and related processes”, Invited speech, International Symposium on Visualization in Joining & Welding Science through Advanced Measurements and Simulation(Visual-JW), Osaka, Japan, 2016, October
[16] S.-J.Na, “Metallurgical and mechanical optimization of welded structures based on CFD process simulations”, Invited speech, IIW 6th Welding Research and Collaboration Colloquium, Hyderabad, India, 2016, April
15] S.-J.Na, “Some issues in CFD simulations of laser keyhole welding”, Invited speech, 18th International Workshop on Process Fundamentals of Laser Welding and Cutting, Hirschegg, Austria, 2016, February
[14] S.-J.Na, “Heat and mass flow in materials welding and its application to mechanical analysis of welded structures”, Keynote speech, International Symposium on Globalization in Joining Technology and Materials Science, Osaka, Japan, 2015, October
[13] S.-J.Na, J.-H.Cheon, D.V.Kiran, D.-W.Cho, “Heat and mass flow in arc welding processes and its application to mechanical analysis of welded structures”, Keynote speech, The 11th International Seminar on Numerical Analysis of Weldability, Graz-Seggau, Austria, 2015, September
[12] S.-J.Na, M.Sohail, S.-W.Han, M.Karhu, V.Kujanpaa, “Flow and element mixing characteristics in laser GMA hybrid welding”, Keynote speech, The 15th Nordic Laser Materials Processing Conference, Lappeenranta, Finland, 2015, August
[11] S.-J.Na, S.-W.Han, M.Sohail, L.Zhang, A.Gumenyuk, M.Rethmeier, M.Karhu, V.Kujanpaa, “Flow and bead formation characteristics in high power laser welding at different welding positions”, Invited speech, Lasers in Manufacturing (LIM2015), Munich, Germany, 2015, June
[10] S.-J.Na, D.-V.Kiran, D.-W.Cho, H.-P.Cheon, “Visualization of multi wire SAW process by CFD simulations”, Invited speech, International Symposium on Visualization in Joining & Welding Science through Advanced Measurements and Simulation(Visual-JW), Osaka, Japan, 2014, November
[9] S.-J.Na, “Visualization of welding processes and its application to design of welded structures”, Houdremont (Plenary) speech, International Conference of 67th Annual Assembly of the International Institute of Welding, Seoul, Korea, 2014, July
[8] S.-W.Han, H.-P.Cheon, J.-H.Cho, L.-J.Zhang, S.-J.Na, “CFD simulations of keyhole laser welding”, Invited speech, the 80th Laser Materials Processing Conference Sponsored by Japan Laser Processing Society, Tokyo, Japan, 2013, December
[7] S.-J.Na, “CFD-simulation of welding processes and its application to prediction of welding distortion”, Keynote speech, 5th International Conference on Welding Science and Engineering, Weihei, China, 2013, October
[6] S.-J.Na, D.-W.Cho, W.-I.Cho, “Visualization of Welding and Joining Processes, Based on CFD – Simulations”, Plenary speech, International Symposium on Visualization in Joining & Welding Science through Advanced Measurements and Simulation(Visual-JW), Osaka, Japan, 2012, November
[5] W.-I.Cho, M.Sohail, S.-J.Na, “Modeling of Keyhole Formation in Laser and Laser Arc Hybrid Welding Based on CFD Simulations”, Sub-plenary speech, International Congress on Applications of Lasers & Electro-Optics, Anaheim, CA, United States of America, 2012, September
[4] D.-W.Cho, S.-J.Na, “Analysis and Optimization of Welding Processes Based on CFD-Simulations: Circumferential Pipe Welding”, Keynote speech, 2nd International Symposium on Computer-Aided Welding Engineering, Jinan, China, 2012, August
[3] S.-J.Na, “Laser and Laser-Arc Hybrid Welding: Fundamental Phenomena based on CFD-Simulations”, Plenary speech, International Welding/Joining Conference, Jeju, Republic of Korea, 2012, May
[2] S.-J.Na, W.-I.Cho, D.-W.Cho, “Simulations of weld pool dynamics and its visualization”, Keynote speech, Visual-JW2010, 27-28, Osaka, Japan, 2010, November
[1] S.-J.Na, “Application and research of arc welding automation in Korea”, Keynote speech, Int. Conf. on Robotic welding, Intelligence and Automation 2010, Shanghai, China, 2010, October