Chun-Min Chang

Senior Algorithm Engineer (ML)

LinkedIn | Google Scholar | Github
Email: twcmchang [at] gmail [dot] com

I am interested in network pruning, quantization and low-precision inference to accelerate deep learning models on top of dedicated hardware blocks. Before coming to the states, I spent wonderful years in delivering deep learning technologies to the healthcare space in Taiwan with Sheng-Wei Chen at Academia Sinica. My recent research was published in Nature Communications, npj Digital Medicine, IEEE International Joint Conference on Neural Networks (IJCNN).


Work Experience

Sr. Algorithm Engineer (ML) at Ambarella Corporation, Santa Clara, U.S.A., 2020/06 - Now

Accelerate model inference by optimizing bit width of tensors in post-training quantization and folding operations in a frozen computation graph. Also, implement specialized primitives and arithemtic operations for various target chips with GPU acceleration.

Machine Learning Engineer at Cardinal Blue Software (PicCollage), Taipei, Taiwan, 2019/01 - 2019/07

Design and deploy lightweight deep learning models on iOS and Android platforms for photo style transfer, photo super-resolution, low-light photo enhancement, and object instance segmentation.

Research Assistant at Academia Sinica (alternative military service), Taipei, Taiwan, 2015/10 - 2018/12

Apply cutting-edge machine learning techniques to interdisciplinary studies, and publish research works in Nature Digital Medicine, Nature Communications, Computer methods and programs in biomedicine.


Publications

Automation of The Kidney Function Prediction and Classification Through Ultrasound-based Kidney Imaging Using Deep Learning

Chin-Chi Kuo, Chun-Min Chang, Kuan-Ting Liu, Wei-Kai Lin, Hsiu-Yin Chiang, Chih-Wei Chung, Meng-Ru Ho, Pei-Ran Sun, Rong-Lin Yang, and Kuan-Ta Chen
npj Digital Medicine 2019 / Paper

We developed a deep learning approach for automatically determining the estimated glomerular filtration rate (eGFR) and chronic kidney disease (CKD) status over 4,505 kidney ultrasound images. Overall CKD status classification accuracy of our model was 85.6% —higher than that of experienced nephrologists (60.3%–80.1%).

Artificial Intelligence Reveals Environmental Constraints on Colour Diversity in Insects

Sipher Wu*, Chun-Min Chang*, Guan-Shuo Mai, Dustin R Rubenstein, Chen-Ming Yang, Yu-Ting Huang, Hsu-Hong Lin, Li-Cheng Shih, Sheng-Wei Chen, and Sheng-Feng Shen
Nature Communications(*equal contribution) 2019 / Paper

Using over 20,000 images with GPS locality information belonging to nearly 2,000 moth species, our approach learned deep representations that accurately predict each species’ mean elevation based on colour and shape, as well as help identify the underlying mechanisms generating this biogeographic pattern.

Efficient and Robust Convolutional Neural Networks via Channel Prioritization and Path Ensemble

Chun-Min Chang, Chia-Ching Lin, and Kuan-Ta Chen
IEEE Joint Conference on Neural Networks (IJCNN) 2019 / Paper

We proposed a novel training algorithm for convolutional neural networks to achieve dynamic inference at run time and enhance model robustness against adversarial attacks without any extra computational cost or memory overhead.

Performance Measurements of Virtual Reality Systems: Quantifying the Timing and Positioning accuracy

Chun-Min Chang, Cheng-Hsin Hsu, Chih-Fan Hsu, and Kuan-Ta Chen
ACM International Conference on Multimedia (ACM MM) 2016 / Paper

We propose the very first non-intrusive measurement methodology for quantifying the timing and positioning accuracy of commodity Virtual Reality (VR) systems. Our methodology considers the VR system under test as a black-box and can work with any VR applications without code instrument or system modification.


Side Projects

Non-invasive Estimation of Fasting Blood Glucose using PPG and ECG Signals

Chun-Min Chang and Kuan-Ting Liu
Collaboration with Applied Science Institute, Academis Sinica, 2018

We leveraged signal processing and machine learning to transform in-the-wild sensor data from the wearable device into intelligent health experiences. Training over 1,200 records from 600 fasting participants, our non-invasive approach showed over 93.5% of test samples in zone A of the Clarke consensus error grid.

Unsupervised Semantic Segmentation of Histology Images

Chun-Min Chang, and Bin Li
Collaboration with Biomedical Engineering, University of Wisconsin-Madison, 2019

We design a unsupervised model for differentiating histology tissue matrices. The learning algorithm is guided by superpixel refinement and deep feature clustering, and beats other unsupervised methods in metrics of accuracy and inference time.