I am a Research Fellow in the Department of the Built Environment, National University of Singapore, working with Prof. Yang Miang Goh. I received my Ph.D. degree in the Department of Automation, Tsinghua University in 2023. As a member of CFINS, I’m supervised by Prof. Qianchuan Zhao.

My research interest lies in smart building and deep learning, including building occupancy detection/estimation, computer vision and generative models. I have published more than 10 papers in top international journals, including Building and Environment, Energy and Buildings, Cell Patterns, etc.

🔥 News

• 2024.11.17: 🎉🎉 Our paper (Corresponding author) is accepted: An experimental comparative study of energy saving based on occupancy-centric control in smart buildings. Irfan Qaisar, Wei Liang, Kailai Sun^*, Tian Xing, Qianchuan Zhao. Building and Environment (BAE). (2025).(Top , SCI, JCR Q1, IF:7.201). (Acceptance Rate: 17%)
• 2024.10.20: 🎉🎉 Our Review paper is accepted: A review of AI edge devices and lightweight CNN and LLM deployment. Kailai Sun^1,*, Xinwei Wang¹, Qianchuan Zhao^*.Neurocomputing. (Top , SCI, JCR Q1, IF:5.5).
• 2024.8.6: 🎉🎉 My paper is accepted: Predicting trucking accidents with truck drivers’ safety climate perception: An in-depth evaluation of the pretrain-then-finetune approach Kailai Sun, Tianxiang Lan, Say Hong Kam, Yang Miang Goh, Yueng-Hsiang Huang. Transportation Research Part F: Traffic Psychology and Behaviour (TRF). (2024).(JCR Q1, SSCI). Code link.
• 2024.7.1: 🎉🎉 My paper is accepted: High-accuracy occupancy counting at crowded entrances for smart buildings. Kailai Sun, Xingwei Wang, Tian Xing, Shaobo Liu^*, Qianchuan Zhao. Energy and Buildings (ENB). (2024).(Top , SCI, JCR Q1, IF:7.093). (Acceptance Rate: 22%) Code link.
• 2024.4.26: 🎉🎉 My paper is accepted: A Two-Stage Masked Autoencoder Based Network for Indoor Depth Completion. Kailai Sun^*, Zhou Yang, Qianchuan Zhao. The IEEE/CVF Conference on Computer Vision and Pattern Recognition 2024.(CVPR). I presented it on Jun 17th, 2024, in Seattle, USA. Oral Presentation. Poster Presentation. Code link.
• 2024.2.24: 🎉🎉 My paper is accepted: DMFF: Deep Multimodel Feature Fusion for Building Occupancy Detection. Kailai Sun^*. Building and Environment (BAE). (2024).(Top , SCI, JCR Q1, IF:7.201). (Acceptance Rate: 17%) Code link.
• 2024.1.26: 🎉🎉 Presentation on NVIDIA Workshop: AI for Climate, AI for Science, and Quantum Workshop by NVIDIA, at National University of Singapore.
• 2023.12: 🎉🎉 Our paper is accepted with a first-round revision. An interpretable clustering approach to safety climate analysis: examining driver group distinction in safety climate perceptions. Kailai Sun, Tianxiang Lan, Yang Miang Goh^*, Sufiana Safiena, Yueng-Hsiang Huang, Bailey Lytle, Yimin He. Accident Analysis and Prevention.(AAP).(2023).(Top , SCI, JCR Q1, IF:5.9).(Acceptance Rate: 13%)
• 2023.09: 🎉🎉 My paper is accepted with a first-round Minor revision.:Building occupancy number prediction: A Transformer approach. Kailai Sun^*, Irfan Qaisar,Muhammad Arslan Khan, Qianchuan Zhao. Building and Environment (BAE). (2023).(Top , SCI, JCR Q1, IF:7.201). (Acceptance Rate: 17%) Code link.
• 2023.07: 🎉🎉🎉 Our large head tracking dataset (including 10 diverse scenes of 50,528 frames with over 2,366,249 heads and 2,358 tracks) is completed. Visualization videos. Our dataset and paper will be available public after review.
• 2023.06: 🎉🎉 Our abstract has been accepted by the 2023 INFORMS Annual Meeting:Learn to Solve Large-scale Job Shop Scheduling by Integrating Machine Learning and Mathematical Optimization.
• 2022.11: 🎉🎉🎉 Cell Press reported our work.Report link.
• 2023.11: I was recognized by ElsevierConnect as a top #OpenAccess contributor! Between 2020–2022, I published 2 open access articles with Elsevier. 1 of my articles was linked to the United Nations Sustainable Development Goals. link

📝 Publications

¹:Co-first authors

^*:Corresponding authors

Under-review Paper

• Toward Pedestrian Head Tracking: A Benchmark Dataset and an Information Fusion Network. Kailai Sun, Xinwei Wang, Shaobo Liu^*, Qianchuan Zhao^*, Gao Huang, Chang Liu.
• We collect and annotate a Chinese large-scale cross-scene dataset (Cchead) for crowded head tracking, including 10 diverse scenes of 50,528 frames with over 2,366,249 heads annotated.
• We present a novel solution and insight for head tracking by leveraging pseudo-multi-source information fusion, achieving SOTA performance.

2024

• HCDN: A Change Detection Network and Dataset for Construction Housekeeping Using Feature Fusion and Large Vision Models. Kailai Sun, Zherui Shao, Yang Miang Goh*, Jing Tian, Vincent J.L. Gan. Code link.
• We propose a change detection dataset to mitigate housekeeping problems in construction sites.
• We designed a novel Housekeeping Change Detection Network (HCDN) with Large Vision Model (LVM) and more effective features fusion, achieving superior performance than existing SOTA methods.
• We integrate HCDN into the proposed housekeeping detection system, which shows its potential in practical construction site situations.

• Bridging the Gap Between Indoor Depth Completion and Masked Autoencoders. Zhou Yang,Kailai Sun^1,*, Qianchuan Zhao.

• A computer vision-based construction housekeeping monitoring system: A two-stage object detection-then-classification approach. Zherui Shao, Kailai Sun, Yang Miang Goh*, Jing Tian, Vincent J.L. Gan.

• Overcoming Imbalanced Safety Data Using Extended Accident Triangle. Kailai Sun, Tianxiang Lan, Yang Miang Goh, Yueng-Hsiang Huang.

• AFSA: Adaptive Modal-Temporal Fusion via Sparse Attention. Ruoyu Wang, Jiaolong Xu, Kailai Sun, Qianchuan Zhao.

Journal Paper

ENB 2020

• A review of building occupancy measurement systems.
  Kailai Sun, Qianchuan Zhao^*, Jianhong Zou. Energy and Buildings (ENB). 216 (2020): 109965. (Top , SCI, JCR Q1, IF:7.093, citations:148, ESI highly cited paper). (Acceptance Rate: 22%)
• Five-years occupancy measurement systems based on cameras, WiFi, PIR sensors, CO2 sensors, electricity sensors are analyzed and discussed.
• The first comprehensive analysis based on different types and installed locations of camera.

Cell Patterns 2022

• Honeycomb: An open-source distributed system for smart buildings. Tian Xing¹, Hu Yan¹, Kailai Sun¹, Yifan Wang, Xuetao Wang and Qianchuan Zhao^*. Patterns.(Cell sub journal)(SCI, JCR Q1, IF:6.5 )(2022). Data link. Code link.
• A bee-inspired, fully distributed, and open-source building IoT solution, has strong flexibility and robustness, multiple functionalities.
• Proposed vision-based deep-learning occupancy measurement system.
• High user acceptance during long-term stable operation.

2025

• A review of AI edge devices and lightweight CNN and LLM deployment. Kailai Sun^1,*, Xinwei Wang¹, Qianchuan Zhao^*. Neurocomputing. (2025). (SCI, JCR Q1, Top, IF:5.5).
• Many AI edge devices with AI accelerators (Nvidia Nano, TX2, Intel NCS2, Google Coral Dev Board, Coral USB, Baidu Edgeboard FZ3, AMD Kria K2, etc) are compared and analyzed.
• Lightweight CNN and large language models, neural network compression, and their deployment on AI edge devices for practical applications, are reviewed.

BAE 2022

• A Fusion Framework of Vision-based Indoor Occupancy Estimation.
  Kailai Sun¹, Peng Liu¹, Tian Xing, Qianchuan Zhao^* and Xinwei Wang. Building and Environment (BAE). 222 (2022): 109354.(Top , SCI, JCR Q1, IF:7.201). Code link. (Acceptance Rate: 17%)
• The first work to develop a three-level fusion framework in vision-based indoor occupancy estimation.
• Our framework achieves state-of-the-art (SOTA) performance through ablation studies on practical building surveillance videos.

BAE 2022

• MPSN: Motion-aware Pseudo-Siamese Network for Indoor Video Head Detection in Buildings. Kailai Sun, Xiaoteng Ma, Peng Liu, Qianchuan Zhao^*. Building and Environment (BAE). 222 (2022): 109354.(Top , SCI, JCR Q1, IF:7.201).Code link. (Acceptance Rate: 17%)
• The first work to jointly train the current frame and the pixel-level motion information into an end-to-end CNN network in head detection.
• We validate its robustness through adversarial experiments with a mathematical solution of small perturbations.

BAE 2024

• DMFF: Deep Multimodel Feature Fusion for Building Occupancy Detection. Kailai Sun^*. Building and Environment (BAE). (2024).(Top , SCI, JCR Q1, IF:7.201). Invited. Code link.
• Multi-model deep learning meets occupancy. Sound, image and environmental data are integrated to detect occupancy.
• To transfer pre-trained AI models and domain knowledge into the building field, We introduce the pretrain-finetune pipeline and propose a Transformer-based multimodel fusion algorithm for occupancy detection.

BAE 2022

• Building occupancy number prediction: A Transformer approach. Kailai Sun^1,*, Irfan Qaisar¹,Muhammad Arslan Khan, Qianchuan Zhao. Building and Environment (BAE). (2023).(Top , SCI, JCR Q1, IF:7.201). Code link. Accepted with a first-round Minor revision. (Acceptance Rate: 17%)
• We publicly provide an actual building operating dataset for six zones.
• Our Transformer-based occupancy prediction algorithm performs superior on our dataset than other existing deep learning algorithms

ENB 2024

• High-accuracy occupancy counting at crowded entrances for smart buildings. Kailai Sun, Xingwei Wang, Tian Xing, Shaobo Liu^*, Qianchuan Zhao. Energy and Buildings (ENB). (2024).(Top , SCI, JCR Q1, IF:7.093). (Acceptance Rate: 22%) Code link.
• The advanced computer vision model for sensing and tracking occupancy heads using surveillance videos.
• The practical occupant-centric control (OCC) for energy efficiency and occupant comfort.
• This research can be generalised to border domains, including building management, flow estimation, safety prevention, etc.

• An interpretable clustering approach to safety climate analysis: examining driver group distinction in safety climate perceptions. Kailai Sun¹, Tianxiang Lan, Yang Miang Goh^*, Sufiana Safiena, Yueng-Hsiang Huang, Bailey Lytle, Yimin He. Code link. Accident Analysis and Prevention.(2023).(Top , SCI, JCR Q1, IF:5.9).(Acceptance Rate: 13%)

• Predicting trucking accidents with truck drivers’ safety climate perception: An in-depth evaluation of the pretrain-then-finetune approach Kailai Sun, Tianxiang Lan, Say Hong Kam, Yang Miang Goh, Yueng-Hsiang Huang. Transportation Research Part F: Traffic Psychology and Behaviour (TRF). (2024).(SSCI, JCR Q1). Code link.

• Indoor occupancy measurement by the fusion of motion detection and static estimation. Kailai Sun, Qianchuan Zhao^*, Ziyou Zhang, and Xinyuan Hu. Energy and Buildings (ENB). 254 (2022): 111593.(Top , SCI, JCR Q1, IF:7.093). (Acceptance Rate: 22%)

• An experimental comparative study of energy saving based on occupancy-centric control in smart buildings. Irfan Qaisar, Wei Liang, Kailai Sun^*, Tian Xing, Qianchuan Zhao. Building and Environment (BAE). 112322.(2025).(Top , SCI, JCR Q1, IF:7.201). (Acceptance Rate: 17%)

• Using knowledge inference to suppress the lamp disturbance for fire detection. Kailai Sun, Qianchuan Zhao^*, and Xinwei Wang. Journal of Safety Science and Resilience (JSSR, JCR Q1, SCI). 2.3 (2021): 124-130.Code link.

• Protocol for a distributed smart building solution using semi-physical simulation. Hu Yan¹, Tian Xing¹, Kailai Sun¹, and Qianchuan Zhao^*. Star Protocols.(Cell sub journal).(2023).(Invited article).

• A Succinct Summary of Vision-based Building Occupancy Estimation. Kailai Sun. Advancements in Civil Engineering & Technology 5 (3). (2023) (IF: 4.982)

• Multi-sensor Based Occupancy Prediction in a Multi-zone Office Building with Transformer.Irfan Qaisar¹ Kailai Sun¹, Qianchuan Zhao^*, Tian Xing, Hu Yan. Buildings. (2023).(SCI, IF:3.324).

• Integrating Machine Learning and Mathematical Optimization for Job Shop Scheduling. Anbang Liu, Peter B. Luh^*, Kailai Sun. IEEE Transactions on Automation Science and Engineering (TASE). (2022).(Top , SCI, IF:6.636).

• MITP-Net: a Deep-learning Framework for Short-term Indoor Temperature Predictions in Multi-zone Buildings. Tian Xing,Kailai Sun, Qianchuan Zhao^*.Building and Environment (BAE). (2023).(Top , SCI, JCR Q1, IF:7.201). (Acceptance Rate: 17%)

• A Learning-Based Method for Computing Control Barrier Functions of Nonlinear Systems With Control Constraints. Ziyou Zhang, Qianchuan Zhao*, Kailai Sun. IEEE Robotics and Automation Letters.(SCI). 2023.

Conference Paper

• Multi-Source Information Fusion network for building occupancy estimation.Kailai Sun, Tian Xing, Xinwei Wang, Zhou Yang, and Qianchuan Zhao^*. In: Alicja Maciejko (eds) Human Factors in Architecture, Sustainable Urban Planning and Infrastructure. AHFE (2023) International Conference. AHFE Open Access, vol 89. AHFE International, USA. http://doi.org/10.54941/ahfe1003687.(Acceptance rate:34%)

• A Two-Stage Masked Autoencoder Based Network for Indoor Depth Completion. Kailai Sun^*, Zhou Yang, Qianchuan Zhao. The IEEE/CVF Conference on Computer Vision and Pattern Recognition 2024. (CVPR). Oral Presentation. Poster Presentation.Code link.

• Research on Multi-temporal Cloud Removal using D-S Evidence Theory and Cloud Segmentation Model. Xinwei Wang¹, Kailai Sun¹, Qianchuan Zhao^*, and Jianhong Zou. The CAAI International Conference on Artificial Intelligence (CICAI). 2022. (Acceptance rate:34%) Poster Presentation.

• A Goal-conditioned Reinforcement Learning Algorithm with Environment Modeling. Zhe yu¹, Kailai Sun¹, Chenghao Li, Dianyu Zhong, Yang Yiqin, Qianchuan Zhao^*.Chinese Control Conference.(2023).

• Attendance and security system based on building video surveillance. Kailai Sun, Qianchuan Zhao^*, Jianhong Zou, Xiaoteng Ma. International Conference on Smart City and Intelligent Building (ICSCIB). Springer, Singapore, 2018.

• Visual feedback system for traditional chinese medical massage robot. Kailai Sun, Qianchuan Zhao^*, Zhenming Yang, Xiuwei Xu. In 2019 Chinese Control Conference (CCC). pp. 6379-6385. IEEE, 2019.Code link.

• A multi-objective optimization of PV/ST-GSHP system based on office buildings. Yu Fu, Haiyang Lin, Kailai Sun, Qie Sun^*, Ronald Wennersten. Energy Procedia. 152 (2018): pp. 71-76.

📖 Educations

• 2023.08 - present, Research Fellow, Department of the Built Environment, National University of Singapore. Prof. Yang Miang Goh
• 2018.09 - 2023.06, Ph.D., Department of Automation, Tsinghua University. Prof. Qianchuan Zhao
• 2022.05, visiting student, Electrical & Computer Engineering, University of Illinois Urbana-Champaign. Prof. Tamer Basar <!–
• 2015.09 - 2018.06, Bachelor, Ye Peida lab, Beijing University of Posts and Telecommunications (BUPT).
• 2014.09 - 2018.06, Bachelor, Department of Automation, Beijing University of Posts and Telecommunications (BUPT). –>

  💻 Projects

• National Natural Science Foundation of China under Grant No. 62192751 and 61425024
• New generation intelligent building platform (National Key Research and Development Project of China under Grant 2017YFC0704100)
• Energy Internet Planning, Operation and Trading (National Key Research and Development Project of China under Grant 2016YFB0901900)
• National Science Foundation of China (Grant No. 52172308), Department of Transport of Hubei Province
• The 111 International Collaboration Program of China under Grant No. BP2018006
• The National Innovation Center of High-Speed Train R&D project (CX/KJ-2020-0006)
• Satellite remote sensing image interpretation technology and system based on artificial intelligence (2019 Major Science and Technology Program for the Strategic Emerging Industries of Fuzhou, Grant BNR2019TD01009)
• Huawei company-Control security issue literature research project
• Ridar-based road vehicle counting and intelligent video surveillance system project
• Intelligent detection and control aircraft system from Tongfang Intelligent Technology Co., ltd
• Evaluation of (Singapore Changi Airport Group and Hua Wei Singapore Company) CAG’s safety model for profiling construction contractors’ safety performance; Ref No.: 2023-0492
• Computer Vision for Housekeeping on Construction Site; Award No.: AISG2-100E-2021-084

✈ Internships

• 2021.06 - 2021.08, Harbin Institute of Technology Robotics Research Institute Co., Ltd, Yangzhou.

🧑‍💻 Workshops

• Poster presentation. 2024.01-26. AI for Climate, AI for Science, and Quantum Workshop by NVIDIA. National University of Singapore.

• Oral Presentation. Poster Presentation. 2024.06-17. Computer Vision in the Built Environment. Seattle, USA.

👨🏽‍🤝‍👨🏼 Collaborators

• Qianchuan Zhao - Professor, Department of Automation, Tsinghua University.
• Yang Miang Goh－Associate Professor, Department of the Built Environment, National University of Singapore.
• Kang Jian - Professor, Bartlett School Env, Energy & Resources, University College London.
• Huang Gao-Associate Professor, Department of Automation, Tsinghua University.
• Jinhua Zhao- Professor, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology.
• Shaobo Liu - Associate Professor, Intelligent Transportation Systems Research Center, Wuhan University of Technology.
• Peter Luh - Professor, Board of Trustees Distinguished Professor Emeritus, University of Connecticut.
• Yueng-hsiang Huang-Associate Professor, Oregon Institute of Occupational Health Sciences, Oregon Health and Sciences University.
• Xiaoteng Ma - Ph.D., Department of Automation, Tsinghua University.
• Anbang Liu - Ph.D. candidate , Department of Automation, Tsinghua University.

🎖 Honors and Awards

Scholarship

• 2022.12 The first prize of Tsinghua University Weimin Zheng Scholarship (Top 1%)
• 2022.11 Tsinghua University - Lingjun Pilot Scholarship
• 2021.11 Tsinghua Scholarship for Overseas Graduate Studies
• 2019.10 The first prize of Tsinghua University Comprehensive Scholarship (Top 1%)
• 2015.06 & 2016.06 Haohan company Scholarship (Top 1%)
• 2015.09 & 2016.09 & 2017.09 National Encouragement Scholarship (Top 3%)

Student

• 2023.06 Outstanding graduates of Department of Automation Tsinghua University (Top 17%)
• 2018.06 Outstanding graduates of Beijing ordinary colleges and universities (Top 1%)
• 2023.06 Academic Excellence Award in System Engineering Institution, Department of Automation, Tsinghua University
• 2018.06 Excellent Student Cadre (Top 3%)
• 2015.09 & 2016.09 & 2017.09 Merit Student (Top 3%)

Competition

• 2017 American Undergraduate Mathematical Contest in Modeling Honorable Mention
• 2015.11 The second prize of the Chinese National Undergraduate Mathematical Contest
• 2016.06 The first prize in the Beijing Division of the Chinese National Undergraduate Mathematical Contest in Modeling
• 2016.07 The second prize in the Beijing Division of the National Undergraduate Electronic Design Competition
• 2022 Best Researcher Award for the contribution and honourable achievement in innovative research. International Research Awards on New Science Inventions NESIN 2022 Awards.

✒️ Reviewer

Journal: IEEE Transactions on Control Systems Technology, IEEE Internet of Things Journal, Building and Environment, Results in Control and Optimizationm, Scientific Programming, Scientific Reports, The Journal of Supercomputing, Journal of Process Mechanical Engineering, etc.

Conference:IEEE International Conference on Robotics and Automation, The World Congress of the International Federation of Automatic Control, etc.

📚 Book

Participated in the translation of the book: Bertsekas, Dimitri. Convex optimization algorithms. Athena Scientific. 2015.

👨‍🏫 Teaching

Teaching assistant for “automatic control theory” for 8 times (4 years).

📞 Contact

Department of Built Environment
National University of Singapore
SDE2-02-07
Singapore, 117566 \

Department of Automation
Tsinghua University \

FIT Building 3-624
Beijing, China, 100084
E-mail: skl.2018@tsinghua.org.cn  18813126518@163.com
 

👨‍🏫 Co-supervised students at Tsinghua:

Irfan Qaisar (2022-;Ph.D.)
Muhammad Arslan Khan (2023-;Ph.D.)
Xinwei Wang (2020-;Master; Gewu Tech. company, Xiaomi Company)
Ruoyu Wang (2023-; Master)
Peng Liu (2021-2023; Master)
Zhou Yang (2021-2023; Master; BYD)
Guanyi Wang (2023-;Master; Huawei)
Zhe Yu (2022-2023; Master)
Zaixian Han (2020; Bachelor; Korea)
Meiling Piao (2019; Bachelor; Korea)
Xi Miao (2023-;Bachelor; U.S)