Portrait of Jiacheng Liu — ./black_selfie.jpg

Jiacheng Liu 刘佳成

role: Ph.D. student, Information Science (year 2)
lab: SciFi Lab, Cornell University
advisor: Prof. Cheng Zhang
focus: wearable sensing · activity detection · assistive devices
location: Gates Hall 239, Ithaca, NY

My research centers on AI-assisted sensing technologies, with a particular emphasis on wearable form factors. My work focuses on activity-detection systems and assistive devices that provide unobtrusive, seamless monitoring and support.

Before Cornell, I earned a Bachelor of Engineering in Creative Design and Intelligent Engineering (CDIE) at Xinya College, Tsinghua University. I gained research experience in multiple labs, including the Pervasive HCI Group and the Future Lab.

--github --googlescholar --orcid --linkedin --cv.pdf

tail -n 8 updates.log

2026-08-26 NEWS 🎉 Our dataset paper SoniSpeech: A Large-Scale Open-Vocabulary Tri-Modal Dataset for Wearable Silent Speech Interfaces was accepted to Interspeech 2026. The dataset is available on Cornell eCommons.
2026-08-21 NEWS 💼 I wrapped up my summer internship at BehaviorAI, where I worked on behavior-tracking models, signal quality control, and the in-house data-collection software.
2026-08-03 NEWS 🎉 Our paper PPG as a Bridge: Cross-Device Authentication for Smart Wearables with Photoplethysmography was accepted to IMWUT 2026.
2026-06-13 NEWS 💼 I joined BehaviorAI (founding team) in New York City as a Research Intern.
2025-06-20 AWARD 🏆 I was awarded the Outstanding Undergraduate Thesis.
2025-06-20 AWARD 🏵 I was awarded the Xinya College Academic Excellence Award.
2025-04-03 NEWS 🎉 I will be joining the SciFi Lab at Cornell University as a Ph.D. student in the Department of Information Science.
2025-02-01 SUBMIT 📩 I have submitted PPG-based Authentication on Smartwatches in Daily Scenarios to IMWUT'25 full paper track.

cat research_question.md

How can we integrate AI with sensing systems to develop early-detection systems and assistive devices for everyday use, providing unobtrusive and seamless health support for individuals with diverse health conditions?

Research interests: wearable sensing and ubiquitous computing, human-centered AI, accessible interaction and health applications

open publications/ --preview

6 items · ↑ ↓ or j / k to browse · click a row to open the paper · * indicates co-first author

PPG as a Bridge: Cross-Device Authentication for Smart Wearables with Photoplethysmography

Jiacheng Liu*, Jiankai Tang*, Guangye Zhao, Ruichen Gui, Songqin Cheng, Taiting Lu, Jian Liu, Weiqiang Wang, Mahanth Gowda, Yuanchun Shi, Yuntao Wang

IMWUT 2026 · Accepted Google Scholar

→ full publication list, by year

cat service.log # reviewing and programme committees

Reviewer ACM CHI · 2026
Reviewer ACM IMWUT · 2026

cat teaching.log # courses I have assisted

INFO 4340/5440 App Design and Prototyping Spring 2026 Teaching Assistant · Instructor: Prof. Kyle Harms
INFO 1300 Introductory Design and Programming for the Web Fall 2025 Teaching Assistant · Instructor: Prof. Kyle Harms

cat honors.log # awards and research funding

awards/

Outstanding Undergraduate Thesis Jul 2025Tsinghua University · awarded to a single student in the cohort
Xinya College Academic Excellence Award Jul 2025Tsinghua University
Tsinghua Friendship – Luo Yuehua Scholarship Nov 2024awarded to 3 students at the college level
Tsinghua Friendship – Toyota Scholarship Oct 2023awarded to 1 student at the college level
Passion for Reading Scholarship Oct 2022awarded to 2 students at the college level