E-mail : jinseuk56@gmail.com
ORCID : 0000-0002-9558-3469
GitHub Repository : https://github.com/jinseuk56

🔰Education

Ph.D.
Materials Science and Engineering, Seoul National University, South Korea
2017.03-2022.08 Combined MS/PhD
(Advisor: Prof. Miyoung Kim)

B.S.
Materials Science and Engineering, Seoul National University, South Korea
2009.03-2015.08

🔰Research Experience

Postdoctoral Research Associate (2024.03-Present)
Funded by the InFUSE Prosperity partnership
electron Physical Science Imaging Centre (ePSIC)
Diamond Light Source, Harwell Campus, Didcot, United Kingdom

Postdoctoral Research Associate (2022.09-2024.02)
Research Institute of Advanced Materials, Seoul National University, Seoul, South Korea

🔰Teaching Experience

Workshop | Lecturer | Jul. 20. 2023 | Korean Society of Microscopy

• 28th TEM Workshop, Jul. 18. 2023–Jul. 21. 2023, Korean Society of Microscopy
• Lecture Title: Machine learning in TEM analysis: Basics and Applications
• Delivered a lecture about applications of machine learning to TEM analysis

Workshop | Lecturer | Jul. 28. 2022–Jul. 29. 2022 | Korean Society of Microscopy

• 27th TEM Workshop, Jul. 26. 2022–Jul. 29. 2022, Korean Society of Microscopy
• Lecture Title: STEM-derived multi-dimensional data processing in Python-integrated GMS 3
• Delivered a lecture and a practical session about data processing and analysis of multi-dimensional STEM data

Lecture | Lecturer | 2020 Fall Semester | Seoul National University

• Lecture Title: Fundamentals of Computer Science (Department of Materials Science and Engineering)
• Delivered a lecture about the basics of Python programming to freshmen

🔰Industry Experience

Semiconductor Engineer (2015.07-2016.07)
SK Hynix (2091, Gyeongchung-daero, Bubal-eup, Icheon-si, Gyeonggi-do, South Korea)
Process integration and wafer-level reliability test for NAND flash memory

🔰Skills

(S)TEM Experiment/Analysis

• Themis Z, Tecnai F20 (Thermo Fisher Scientific), JEM-2100F (Jeol)
• Imaging (TEM/STEM/4D-STEM) & analytical techniques (EELS/EDS)
• Analysis of structure-property relationship
  • Atomic structure & structural defect analysis
  • Amorphous structure analysis (RDF & FEM)
  • Electronic structure & quantitative chemical analysis
  • Tomographic reconstruction & visualization

Development of Computational Tools for (S)TEM Analysis

• Programming (Python/DigitalMicrograph) for (S)TEM analysis
• Application of machine learning algorithms to (S)TEM data analysis
  • Extraction of fundamental/hidden features from microscopy datasets
  • Deep learning, dimensionality reduction, cluster analysis, and their combinations
• Data processing/analysis of STEM-derived multi-dimensional data
  • Electron tomography (feature extraction/tomographic reconstruction)
  • 4D-STEM data processing/analysis

🔰Research Interests

Data Science for Microscopy Analysis

• Machine learning application to microscopic analysis

Development of Computational Methods for Post-processing of Microscopy Data

• Enhancement of SNR for low-dose experiments
• Correction of scanning artifacts

Investigation of 3D Structure-Property Relationships of Materials through Multi-dimensional STEM Techniques

🔰Publication

First Author

(†: authors who equally contributed, *: corresponding author)

• Ryu, J.†, S. Lee†, S. Kim, Y.-C. Joo, M. Kim*, “Correlative study between the local atomic and electronic structures of amorphous carbon materials via 4D-STEM and STEM-EELS”, Applied Physics Letters, 121, 042101 (2022)
• Ryu, J., H. Kim, R. M. Kim, S. Kim, J. Jo, S. Lee, K. T. Nam, Y.-C. Joo, G.-C. Yi, J. Lee, M. Kim*, “Dimensionality reduction and unsupervised clustering for EELS-SI”, Ultramicroscopy, 231, 113314 (2021)
• (Submitted) Jo†, J., J. Ryu†, J.-H. Huh, H. Kim, D. H. Seo, J. Lee, M. Kwon, S. Lee*, K. T. Nam*, M. Kim*. “Direct three-dimensional observation of plasmonic near-fields in a nanoparticle with circular dichroism”

Contributed Paper

• Park, S., T. Jang, S. Choi, Y. H. Lee, K. H. Cho, M. Y. Lee, H. Seo, H.-K. Lim, Y. Kim, J. Ryu, S. W. Im, M. Kim, G.-S. Park, M. Kim, K. Jin, S. H. Kim, H. Kim, K. T. Nam*, “Iridium-Cooperated, Symmetry-Broken Manganese Oxide Nanocatalyst for Water Oxidation”, Journal of the American Chemical Society, 145, 49, 26632–26644 (2023)
  • Contribution: Completed phase identification and quantitative chemical analysis of manganese oxide nanoparticles via electron diffraction and electron energy loss spectroscopy
• Kim, S., U.-G. Kim, J. Ryu, D.-K. Kim, M. Kim, Y.-C. Joo*, S.-Y. Lee*, “Boron-doped amorphous carbon deposited by DC sputtering for a hardmask: microstructure and dry etching properties”, Applied Surface Science, 637, 157895 (2023)
  • Contribution: Implemented EELS analysis of the near-edge structures of carbon and boron atoms
• Oh, J., S.-Y. Lee, H. Kim, J. Ryu, B. Gil, J. Lee, M. Kim*, “Overcharge-induced Phase Heterogeneity and Resultant Twin-like (0003) Layer Deformation in Lithium Cobalt Oxide Cathode for Lithium-ion Batteries”, Advanced Science, 9, 32, 2203639 (2022)
  • Contribution: Achieved noise reduction of EELS spectra using a dimensionality reduction method
• Yoon, S., H. Seo, K. Jin, H. G. Kim, S.-Y. Lee, J. Jo, K. H. Cho, J. Ryu, A. Yoon, Y.-W. Kim, J.-M. Zuo, Y.-K. Kwon, K. T. Nam, M. Kim*, “Atomic reconstruction and Oxygen Evolution Reaction of Mn₃O₄ nanoparticles”, The Journal of Physical Chemistry, 13, 8336-8343 (2022)
  • Contribution: Created a program code for feature extraction from 4D-STEM data using a dimensionality reduction method

🔰Conference & Award

• (Oral Presentation) Ryu, J., J. Jo, H. Kim, K. T. Nam, M. Kim*, “GPU-based fast reconstruction and DL-based feature extraction for EELS tomography”, The 20th International Microscopy Congress, Busan, South Korea (2023)
• (Invited talk) Ryu, J. (on behalf of Prof. Miyoung Kim), G. Kim, S. Lee, M. Kim*, “Exploring ionic migration and structural evolution in dielectric devices”, The 20th International Microscopy Congress, Busan, South Korea (2023)
• (Oral Presentation) Ryu, J., Lee, S. Kim, Y.-C. Joo, M. Kim*, “A comprehensive nanoscale characterization of amorphous carbon films through STEM-EELS and 4D-STEM”, The 20th International Microscopy Congress, Busan, South Korea (2023)
• (Invited talk) Ryu, J., J. Jo, S. Lee, M. Kim, “Unsupervised learning strategies for extracting features from STEM-derived multi-dimensional data”, 2023 Korea Society of Microscopy Spring Conference, Daejeon, South Korea (2023)
• (Poster presentation) Ryu, J., S. Lee, S. Kim, I. Yoo, Y.-C. Joo, M. Kim*, “A machine-learning approach to characterization of amorphous materials with EELS-SI and 4D-STEM”, 2022 Materials Research Society Spring Meeting, Hawaii, United States (2022)
• (Poster presentation) Jo, J., K. MacArthur, J. Ryu, H. Kim, S. Collins, K. Müller-Caspary, K. Nam, M. Kim, R. E. Dunin-Borkowski*, “Three-dimensional characterization of nanoparticles with simultaneously acquired bright-field, dark-field, and secondary electron signals in STEM”, PICO 2021, Virtual Meeting (2021)
• (Oral presentation) Ryu, J., Jo, J. Lee, M. Kim*, “Feature extraction and reconstruction of electron energy loss spectroscopy by non-negative matrix factorization”, Asia Pacific Microscopy Congress 12, Hyderabad, India (2020)
• Excellence Prize, Best Paper Award, Seoul National University & Samsung Electronics R&DB Foundation, South Korea (2021)