I recieved the Ph.D. degree in electrical and computer engineering, with a concentration in signal processing and machine learning, from University of Michigan in 2020. From Sep. 2020 to Jan. 2022, I worked for Siemens Healthineers as a senior AI scientist. I am now an assistant professor in the Department of Electronic Engineering at Inha University.

Curriculum Vitae (05/2023)
Thesis (Advisor: Jeffrey Fessler, Yuni Dewaraja)

Find me on  Scholar,  LinkedIn.

Image reconstruction and analysis
Generative model
Unsupervised learning

I am recruiting 4th year undergraduate students who intend to apply for the ECE graduate program at Inha Unversity.
If you are interested in my research area, please contact me via email.

Hongki Lim, Yuni Dewaraja, and Jeffrey Fessler.
SPECT reconstruction with a trained regularizer using CT-side information: Application to 177Lu SPECT imaging.
IEEE Transactions on Computational Imaging, 2023. submitted

Il Yong Chun, Zhengyu Huang*, Hongki Lim*, and Jeffrey Fessler.
Momentum-Net: Fast and convergent iterative neural network for inverse problems.
IEEE Transactions on Pattern Analysis and Machine Intelligence, 45(4):4915-4931, Apr. 2023.

Haowei Xiang, Hongki Lim, Jeffrey Fessler, and Yuni Dewaraja.
A deep neural network for fast and accurate scatter estimation in quantitative SPECT/CT under challenging scatter conditions.
European Journal of Nuclear Medicine and Molecular Imaging, 47:2956–2967, May. 2020.

Hongki Lim, Il Yong Chun, Yuni Dewaraja, and Jeffrey Fessler.
Improved low-count quantitative PET reconstruction with an iterative neural network.
IEEE Transactions on Medical Imaging, 39(11):3512-3522, Nov. 2020.

Hongki Lim, Jeffrey Fessler, Scott Wilderman, Allen Brooks, and Yuni Dewaraja.
Y-90 SPECT maximum likelihood image reconstruction with a new model for tissue-dependent bremsstrahlung production: A proof-of-concept study.
Physics in Medicine & Biology, 63(11):115001, Jun. 2018.

Hongki Lim, Yuni Dewaraja, and Jeffrey Fessler.
A PET reconstruction formulation that enforces non-negativity in projection space for bias reduction in Y-90 imaging. [code]
Physics in Medicine & Biology, 63(3):035042, Feb. 2018.

(The asterisks (*) indicate equal contributions.)

Hongki Lim, Yuni Dewaraja, and Jeffrey Fessler.
Joint low-count PET/CT segmentation and reconstruction with paired variational neural networks.
Proc. SPIE Medical Imaging: Phys. Med. Im., Feb. 2020. [Slides]

Haowei Xiang, Hongki Lim, Jeffrey Fessler, Yuni Dewaraja.
SPECT/CT scatter correction using deep learning: implementation in Y-90 imaging.
Proc. IEEE Nuc. Sci. Symp. Med. Im. Conf., Oct. 2019.

Hongki Lim, Il Yong Chun, Jeffrey Fessler, and Yuni Dewaraja.
Improved low count quantitative SPECT reconstruction with a trained deep learning based regularizer.
J. Nuc. Med. (Abs. Book), 60(s1): 42. 2019. [Slides]

Hongki Lim, Zhengyu Huang, Jeffrey Fessler, Yuni Dewaraja, Il Yong Chun.
Application of trained Deep BCD-Net to iterative low-count PET image reconstruction.
Proc. IEEE Nuc. Sci. Symp. Med. Im. Conf., pp. 1-4, Nov. 2018. [Slides]

Se Young Chun, Hongki Lim, Jeffrey Fessler, Yuni Dewaraja.
On Parameter Selection for Joint Spectral Reconstruction in Y90 SPECT.
Proc. IEEE Nuc. Sci. Symp. Med. Im. Conf., pp. 1-4, Nov. 2018.

Il Yong Chun, Hongki Lim, Zhengyu Huang, and Jeffrey Fessler.
Fast and convergent iterative signal recovery using trained convolutional neural networks.
Proc. Allerton, pp 155-159. IEEE, 2018.

Hongki Lim, Jeffrey Fessler, Yuni Dewaraja.
Joint dual photopeak image reconstruction in Lu-177 SPECT.
Eur. J. Nuc. Med. Mol. Imaging, 45:S95-S96, Oct. 2018. [Slides]

Hongki Lim, Kyungsang Kim, Quanzheng Li, Jeffrey Fessler, Yuni Dewaraja.
Bias reduction in Y-90 PET with reconstruction that relaxes the non-negativity constraint.
J. Nuc. Med. (Abs. Book), 59(s1): 580. 2018. [Slides]

Hongki Lim, Yuni Dewaraja, Jeffrey Fessler.
Reducing bias in Y-90 PET images by enforcing non-negativity in projection space.
Proc. IEEE Nuc. Sci. Symp. Med. Im. Conf., pp. 1-4, 2017. [Slides]

Hongki Lim, Neal Clinthorne, Maurizio Conti, Jeffrey Fessler, Yuni Dewaraja.
Quantitative Y-90 PET for dosimetry in radioembolization.
Eur. J. Nuc. Med. Mol. Imaging, 44(s2):S398, Oct. 2017.

Hongki Lim, Yuni Dewaraja, Jeffrey Fessler.
Y-90 SPECT maximum likelihood image reconstruction with a new model for tissue-dependent bremsstrahlung production.
J. Nuc. Med. (Abs. Book), 58(s1):746, May 2017. [Slides]

Hongki Lim, Yuni Dewaraja.
Impact of Tc-99m SPECT reconstruction methods on lung shunt and lesion/normal liver activity quantification in radioembolization.
J. Nuc. Med. (Abs. Book), 58(s1):1032, May 2017. [Poster]