Biomedical Engineering

    Wearable sensors

        • Human activity recognition (HAR)

        • Interpretable modeling of human activities: Motion Units

        • Body area network (BAN) / (wearable) body sensor network (BSN / WBSN)

    Physiological signal acquisition and analysis

        • Bioelectric signals (EXG): ECG/EKG, EMG, EEG, EOG, EGG, ERG, etc.

        • Biooptical signals: PPG (BVP, SpO2, pulse, etc.), fNIRs, Imaging

        • Biomechanical/biokinetic/biomagnetical signals: force, baro, acceleration, gyro, magnetism, GPS

        • Bioacoustic signals: waves, sonar

        • Biothermal signals: temperature, heatmap

        • Biochemical signals: blood glucose, insulin

    Human-computer interaction (HCI) interface and methods

        • Biosignal and user interface

        • Biosignal for Metaverse: VR, AR, MR, XR

Interpretable Approaches of Machine Learning

    Time-series processing

        • Open-source time-series feature extraction code library :TSFEL

        • Open-source time-series subsequence search code library: TSSEARCH

        • Self-similarity matrix algorithm: SSM

    Outlier detection

        • Adaptive mini-minimum spanning tree generation: MMOD

        • Minimum spanning tree and medoid selection: MS2OD

    Feature engineering

        • Handcrafted feature engineering: windowing, extraction, overlapping, and selection

        • Feature stacking and dimensionality reduction

        • High-level interpretable feature design

    Hidden Markov models (HMM)

        • Interpretatble sequence partitioning

        • HMM knowledge transfer from automatic speech recognition

    Cross-disciplinary applications of AI

New Energy and Power Grid Industry Driven by AI and Big Data

    Smart grid

        • Small-current grounding fault detection

        • Automated operation and maintenance

        • Wearable intelligent inspection

    Smart buildings

        • Energy efficiency analysis and improvement

        • Waste heat recovery

        • Multi-criteria optimization and evaluation for building energy

    Solar assisted heat pump system

Music and Computer Science; Ethnomusicology

    Musicology-based modeling

        • Symbolic music signal processing and analysis

        • Pitch histogram

        • Music information retrieval (MIR)

        • Algorithms and interfaces for assisting amateur singers

    Ethnic music

        • Pentatonic scale

        • Chinese folk music and anhemitonic pentatonic scale

Loochoology

    Loochooan Musicology

        • Loochooan pentatonic scale

        • Looka

    Loochoo's anti-colonial history

[Book]

1. Biomedical Engineering Systems and Technologies. Liu, H. et al. (2025). Springer Nature Switzerland.

2. Sensors for Human Activity Recognition II. Liu, H., Gamboa, H., and Schultz, T. (2025). MDPI.

3. Proceedings of the 17th International Joint Conference on Biomedical Engineering Systems and Technologies – (Volume 1). Guarino, M. P., Hotta, K., Yousef, M., Liu, H., Saggio, G., Fred, A., and Gamboa, H. (2024). INSTICC.

4. Sensors for Human Activity Recognition. Liu, H., Gamboa, H., and Schultz, T. (2023). MDPI.

5. Biosignal Processing and Activity Modeling for Multimodal Human Activity Recognition. Liu, H. (2021). PhD thesis, University of Bremen.

[Chapter]

1. EMG-Based Action Unit Recognition: Feature Engineering, Machine Learning, and Real-Time Classification. Liu, H.*, Veldanda, A., Koschke, R., Schultz, T., and Küster, D.* (2025). Biomedical Engineering Systems and Technologies, Springer Nature Switzerland.

2. Muscle Synergy and Co-Contraction Effects on Joystick Manipulation. Ouyang, C., Cai, L.*, Yan, S., Zhang, T., Zhu, J., Chen, L., and Liu, H.* (2025). Biomedical Engineering Systems and Technologies, Springer Nature Switzerland.

3. High-Level Features for Human Activity Recognition and Modeling. Hartmann, Y.*, Liu, H., and Schultz, T. (2023). Biomedical Engineering Systems and Technologies. Springer Nature Switzerland.

4.  EMG-based Action Unit Recognition of Subtle and Intense Expressions: Towards Single-Trial Classification Models. Küster, D.*, Rammonhan, R. A., Liu, H., Schultz, T., and Koschke, R. (2026). Biomedical Engineering Systems and Technologies, Springer Nature Switzerland.

[Journal] ( = ESI Hot Paper (top 0.1%);   = ESI Highly-Cited Paper (top 0.1%))

1.   Taxonomy and Real-Time Classification of Artifacts during Biosignal Acquisition: A Starter Study and Dataset of ECG. Liu, H.*, Zhang, S., Gamboa, H., Xue, T., Zhou, C., and Schultz, T. (2024). IEEE Sensors Journal, 24(6):9162-9171. ISSN: 1530-437X.

2.   MS2OD: Outlier Detection Using Minimum Spanning Tree and Medoid Selection. Li, J., Li, JW, Wang, C., Verbeek F. J.*, Schultz, T., and Liu, H.* (2024). Machine Learning: Science and Technology, 5:015025. IOPscience. ISSN: 2632-2153.

3.   Muscle Synergies in Joystick Manipulation. Cai, L., Yan, S., Ouyang C., Zhang, T., Zhu, J., Chen, L., Ma, X.*, and Liu, H.* (2023). Frontiers in Physiology, 14:1282295. ISSN: 1664-042X.

4.   Outlier Detection Using Iterative Adaptive Mini-Minimum Spanning Tree Generation with Applications on Medical Data. Li, J., Li, JW, Wang, C, Verbeek, F. J.*, Schultz T., and Liu H.* (2023). Frontiers in Physiology, 14:1233341. ISSN: 1664-042X.

5.   Robust Human Locomotion and Localization Activity Recognition over Multisensory. Khan, D., Alonazi, M., Abdelhaq, M.*, Al Mudawi, N., Algarni, A., Jalal, A.*, and Liu, H.* (2024). Frontiers in Physiology, 15:1344887. ISSN: 1664-042X.

6.   Efficient Wi-Fi-Based Human Activity Recognition Using Adaptive Antenna Elimination. Jannat, M.K.A., Islam, M.S., Yang, S-H*, and Liu, H.* (2023). IEEE Access, 11:105440-105454.

7.   Biosensor-Driven IoT Wearables for Accurate Body Motion Tracking and Localization. Almujally, N. A., Khan, D., Al Mudawi, N, Alonazi, M., Alazeb, A., Algarni, A., Jalal, A.*, and Liu, H.* (2024). Sensors 24(10):3032.

8.   Remote Intelligent Perception System for Multi-Object Detection. Alazeb, A., Chughtai, B. R., Al Mudawi, N., Alqahtani, Y., Alonazi, M., Aljuaid, H., Jalal, A.*, and Liu, H.* (2024). Frontiers in Neurorobotics, 18:1398703. ISSN: 1662-5218.

9. Deep Multimodal Biomechanical Analysis for Lower Back Pain Rehabilitation to Improve Patients Stability. Ashraf, A., Wu, Y., Najam, S., Alshehri, M., Alqahtani, Y., Aljuaid, H., Jalal, A.*, and Liu, H.* (co-first) (2025). Frontiers in Bioengineering and Biotechnology, 13:1631910. ISSN: 2296-4185.

10. Aerial Images for Intelligent Vehicle Detection and Classification via YOLOv11 and Deep Learner. Mujtaba, G., Liu, W., Alshehri, M., AlQahtani, Y., Almujally, N. A., and Liu, H.* (2025). Computer, Materials & Continua. Tech Science Press. ISSN: 1546-2218.

11. UAV-Based Intelligent Traffic Surveillance using Recurrent Neural Networks and Swin Transformer for Dynamic Environments. Almujally, N. A., Wu, T., Alhasson, H. F., Hanzla, M., Jalal, A.*, and Liu, H.* (co-first) (2025). Frontiers in Neurorobotics. ISSN: 1662-5218.

12. Integrated Neural Network Framework for Multi-Object Detection and Recognition Using UAV Imagery. Alshehri, M., Xue, T., Mujtaba, G., Alqahtani, Y., Almujally, N., Jalal, A.*, and Liu, H.* (co-first) (2025). Frontiers in Neurorobotics. ISSN: 1662-5218.

13. Dynamic Graph Neural Networks for UAV-Based Group Activity Recognition in Structured Team Sports. Zahra, I., Wu, Y., Alshehri, M., Alqahtani, Y, Aljuaid, H., Jalal, A.*, and Liu, H.* (2025). Frontiers in Neurorobotics. ISSN: 1662-5218.

14. A Novel Multi-Modal Rehabilitation Monitoring Over Human Motion Intention Recognition. Kamal, S., Alshehri, M., Alqahtani, Y., Alshahrani, A., Almujally, N., Jalal, A.*, and Liu, H.* (2025). Frontiers in Bioengineering and Biotechnology. ISSN: 2296-4185.

15. A Hybrid Deep Learning Pipeline for Wearable Sensors-based Human Activity Recognition. Algarni, A., Abro, I. A., Alshehri, M., AlQahtani, Y., Alshahrani, A., and Liu, H.* (2025). Computer, Materials & Continuah. Tech Science Press. ISSN: 1546-2218.

16. ANN-Assisted Optimization of a Solar-to-X System for Green Hydrogen Production, CO₂ Capture, and Methanol-Based Energy Storage. Liu, H.*, Liu, W., Wu, Y., Du, Z., Xue, T., Manesh A. M., Xu, J*, and Jiang, T.* (2025). Energy. Elsevier. ISSN: 0360-5442.

17. A New Synthesized Framework of Artificial Neural Network-Based Sensitivity Analysis for Building Energy Performance: A Case Study of Shanghai, China. Hui Liu*, Yanfeng Wu, Wenbiao Liu, Tingting Xue, and Jun Xu (2025). Building and Environment, 283:113290. Elsevier. ISSN: 0360-1323.

18. Intelligent Biosensors for Human Movement Rehabilitation and Intention Recognition. Rafiq, M., Almujally, N., Algarni, A., Jalal, A.*, and Liu, H.* (2025). Frontiers in Bioengineering and Biotechnology, 13:1558529. ISSN: 2296-4185.

19. A Novel Deep Learner for Human Behavior Prediction over Public Video Surveillance. Alabdullah, B, Fatima, B. B., Alhasson, H. F., Alshehri, M., AlQahtani, Y., Albhassabi, N., and Liu, H.* (2025). IEEE Access, 13:108718-108731.

20. Wearable Sensors-based Assistive Technologies for Patient Health Monitoring. Almujally, N. A., Khan, D., Al Mudawi, N., Alonazi, M., Algarni, A., Jalal, A.*, and Liu, H.* (2025). Frontiers in Bioengineering and Biotechnology, 13:1437877. ISSN: 2296-4185.

21. Multimodal Intelligent Biosensors Framework for Fall Disease Detection and Healthcare Monitoring. Abro, I. A., Alharbi, S. S., Alshammari, N. S., Algarni, S., Almujally, N. A., Jalal, A.*, and Liu, H.* (2025). Frontiers in Bioengineering and Biotechnology, 13:1544968. ISSN: 2296-4185.

22. A Deep Learning Framework for Healthy LifeStyle Monitoring and Outdoor Localization. Rafiq, M., Albhassabi, N., Alhasson, H. F., AlHammadi, D. A., Alshehri, M., Jalal, A.*, and Liu, H.* (2025). IEEE Access. (Early access)

23. Towards Human Modeling for Human-Robot Collaboration and Digital Twins in Industrial Environments: Research Status, Prospects, and Challenges. Xia, G.*, Ghrairi, Z., Wuest, T., Hribernik, K., Heuermann, A., Liu, F., Liu, H., and Thoben, K. (2025). Robotics and Computer-Integrated Manufacturing, 95:103043.

24. Advanced Leaf Classification using Multi-Layer Perceptron for Smart Crop Management. Mumtaz S., Alshehri M., AlQahtani Y., Alshahrani A., Alabdullah, B., Alhasson, H. F., Jalal, A.*, and Liu, H.* (2025). IEEE Access, 13:105579-105589.

25. Multi-Modal Remote Sensory Learning for Multi-Objects over Autonomous Devices. Naseer, A., Almudawi, N., Aljuaid, H., Alazeb, A., Alqahtani, Y., Algarni, A., Jalal, A.*, and Liu, H.* (2025). Frontiers in Bioengineering and Biotechnology, 13:1430222. ISSN: 2296-4185.

26. Thermo-Environ-Economic Analysis of a Novel Solar-Assisted Heat Pump System; Comparison with Conventional Single Stage and Cascaded Air Source Heat Pumps. Afshin, M. M. and Liu, H.* (2025). Energy, 322:135647. Elsevier. ISSN: 0360-5442.

27. Vision Sensor for Automatic Recognition of Human Activities via Hybrid Features and Multi-Class Support Vector Machine. Kamal, S., Alhasson, H. F., Alnusayri, M., Alatiyyah, M., Aljuaid, H., Jalal, A.*, and Liu, H.* (2025). Sensors, 25(1):200.

28. Enhancing Smart Building Performance with Waste Heat Recovery: Supply-Side Management, Demand Reduction, and Peak Shaving via Advanced Control Systems. Liu, H., Du, Z., Xue, T., and Jiang, T.* (2025). Energy and Buildings, 327:115070. Elsevier. ISSN: 0378-7788.

29. Leaf Classification for Sustainable Agriculture and In-Depth Species Analysis. Mumtaz, S., Alhammadi, D. A., Jalal, A.*, and Liu, H.* (2025). IEEE Access, 13:17043-17053.

30. IoT Powered RNN for Improved Human Activity Recognition with Enhanced Localization and Classification. Mudawi, N. A., Azmat, U., Alazeb, A., Alhasson, H. F., Alabdullah, B., Rahman, H., Liu, H.*, and Jalal, A.* (2025). Scientific Reports, 15:10328. Springer Nature. ISSN: 2045-2322.

31. Attention-Driven Emotion Recognition in EEG: A Transformer-Based Approach with Cross-Dataset Fine-Tuning. Ghous, G., Najam, S., Alshehri, M., Alshahrani, A., AlQahtani, Y., Jalal, A.*, and Liu, H.* (2025). IEEE Access, 13:69369-69394.

32. Unmanned Aerial Vehicle based Multi-Person Detection via Deep Neural Network Models. Alshehri, M., Zahoor, L., Alqahtani, Y., Alshahrani, A., Al-Hammadi, D. A.,Jalal, A.*, and Liu, H.* (2025). Frontiers in Neurorobotics, 19:1582995. ISSN: 1662-5218.

33. Advanced Biosignal-RGB Fusion with Adaptive Neurofuzzy Classification for High-Precision Action Recognition. Abro, I. A., Alhasson, H. F., Alharbi, S. S., Alatiyyah, M., AlHammadi, D. A., Jalal, A.*, and Liu, H.* (2025). IEEE Access, 13:57287-57310.

34. Evaluating the Potential of Microdroplet Flow in Two-Phase Biocatalysis: A Systematic Study. Xiang, L., Solarczek, J., Krajka, V., Liu, H., Ahlborn, L., Schallmey, A., and Constantinou, I.* (2025). ACS Applied Materials & Interfaces, 17(3):4776–4787. ACS Publications.

35. A Hybrid Approach for Sports Activity Recognition Using Key Body Descriptors and Hybrid Deep Learning Classifier. Tayyab M., Alateyah, S. A., Alnusayri, M., Alatiyyah, M., AlHammadi, D. A., Jalal, A.*, and Liu, H.* (2025). Sensors, 25(2):441.

36. An Integrated Artificial Intelligence-Driven Approach to Multi-Criteria Optimization of Building Energy Efficiency and Occupants' Comfort: A Case Study. Liu, H., Du, Z., Xue, T., and Jiang, T.* (2025). Journal of Building Engineering, 103:111944. Elsevier. ISSN: 2352-7102.

37. Human Pose Estimation and Event Recognition via Feature Extraction and Neuro-Fuzzy Classifier. Hanzla, M., Alshammari, N. S., Alharbi, S. S., Wahid, W., Almujally, N. A., Jalal, A.*, and Liu, H.* (2025). IEEE Access, 13:37328-37343.

38. Drone-based Public Surveillance using 3D Point Clouds and Neuro-Fuzzy Classifier. Abbas, Y., Alarfaj, A. A., Alabdulqader, E. A., Algarni, A., Jalal, A., and Liu, H.* (2025). Computer, Materials & Continua, 82(3):4759-4776. Tech Science Press. ISSN: 1546-2218.

39. Remote Sensing Surveillance using Multilevel Feature Fusion and Deep Neural Network. Zahoor, L., Alhasson, H. F., Alnusayri, M., Alatiyyah, M., AlHammadi, D. A., Jalal, A.*, and Liu, H.* (2025). IEEE Access, 13:38282-38300.

40. TPRO-NET: An EEG-Based Emotion Recognition Method Reflecting Subtle Changes in Emotion. Zhang, X., Cheng, X.*, and Liu, H.* (2024). Scientific Reports, 14:13491. Springer Nature. ISSN: 2045-2322.

41. Semantic Segmentation and YOLO Detector over Aerial Vehicle Images. Quresh, A. M., Butt, A. H., Alazeb, A., Al Mudawi, N., Alonazi, M., Almujally, N. A., Jalal, A., and Liu, H.* (2024). Computer, Materials & Continua, 80(2):3315-3332. Tech Science Press. ISSN: 1546-2218.

42. Template-Based Synergy Extrapolation Analysis for Prediction of Muscle Excitations. Li, K., Wang, D., Chen, Z, Guo, D, Pan, S., Liu, H., Zhou, C.*, and Ye, X.* (2024). Physiological Measurement, 45(9):095016. IOPScience.

43. A Robust Multimodal Detection: Physical Exercise Monitoring in Long-Term Care Environments. Al Mudawi, N., Batool M., Alazeb A., Alqahtani Y., Almujally, N. A., Algarni A., Jalal, A.*, and Liu, H.* (2024). Frontiers in Bioengineering and Biotechnology, 12:1398291. ISSN: 2296-4185.

44. Robust Human Interaction Recognition Using Extended Kalman Filter. Jalal, A., Bukht, T. F. N., Alazeb, A., Al Mudawi, N., Alabdullah, B, Alnowaiser, K., and Liu, H.* (2024). Computer, Materials & Continua, 81(2):2987-3002. Tech Science Press. ISSN: 1546-2218.

45. Innovative Healthcare Solutions: Robust Hand Gesture Recognition of Daily Life Routines Using 1D CNN. Al Mudawi, N., Ansar, H., Alazeb, A., Aljuaid, H., Alqahtani, Y., Algarni, A., Jalal, A.*, and Liu, H.* (2024). Frontiers in Bioengineering and Biotechnology, 12:1401803. ISSN: 2296-4185.

46. Human Activity Recognition, Monitoring, and Analysis Facilitated by Novel and Widespread Applications of Sensors. Liu, H.*, Gamboa, H., and Schultz, T. (2024). Sensors, 24(15):5250.

47. Multi-Modal Remote Perception Learning for Object Sensory Data. Almujally, N. A., Rafique, A. A., Mudawi, N. A., Alazeb, A., Alonazi, M., Algarni, A., Jalal, A.*, and Liu, H.* (2024). Frontiers in Neurorobotics, 18:1427786. ISSN: 1662-5218.

48. Enhanced Data Mining and Visualization of Sensory-Graph-Modeled Datasets through Summarization. Hashmi, S. J., Alabdullah, B., Al Mudawi, N., Algarni, A., Jalal, A.*, and Liu, H.* (2024). Sensors, 24(14):4554.

49. Understanding Naturalistic Facial Expressions with Deep Learning and Multimodal Large Language Models. Bian, Y., Küster, D., Liu H., and Krumhuber, E. G.* (2024). Sensors, 24(1):126.

50. Cardiorespiratory Response to Workload Volume and Ergonomic Risk: Automotive Assembly Line Operators’ Adaptations. Furk, D., Silva, L.*, Dias, M., Fujão, C., Probst, P., Liu, H., and Gamboa, H. (2024). Applied Sciences, 14(9):3921.

51. Hybrid Modeling on Reconstitution of Continuous Arterial Blood Pressure Using Finger Photoplethysmography. Shi, W., Zhou, C., Zhang, Y., Li, K., Ren, X., Liu, H.*, and Ye, X.* (2023). Biomedical Signal Processing and Control, 85:104972. Elsevier. ISSN: 1746-8094.

52. Sensor-Based Human Activity and Behavior Research: Where Advanced Sensing and Recognition Technologies Meet. Liu, H.*, Gamboa, H., and Schultz, T. (2023). Sensors, 23(1):125.

53. Feature-Based Information Retrieval of Multimodal Biosignals with a Self-Similarity Matrix: Focus on Automatic Segmentation. Rodrigues, J.*., Liu, H.* (co-first), Folgado, D., Belo, D., Schultz, T., and Gamboa, H.* (2022). Biosensors, 12(12):1182. MDPI. ISSN: 2079-6374.

54. Bell Shape Embodying Zhongyong: The Pitch Histogram of Traditional Chinese Anhemitonic Pentatonic Folk Songs. Liu, H.*, Jiang, K., Gamboa, H., Xue, T., and Schultz, T. (2022). Applied Sciences, 12(16):8343.

55. TSSEARCH: Time Series Subsequence Search Library. Folgado, D. Barandas, M., Antunes, M., Nunes, M. L., Liu, H., Hartmann, Y., Schultz, T., and Gamboa, H. (2022). SoftwareX, 18:101049. Elsevier.

56. CSL-SHARE: A Multimodal Wearable Sensor-Based Human Activity Dataset. Liu, H.*, Hartmann, Y., and Schultz, T. (2021). Frontiers in Computer Science, 3:759136.

57. TSFEL: Time Series Feature Extraction Library. Barandas, M., Folgado, D., Fernandes, L., Santos, S., Abreu, M., Bota, P., Liu, H., Schultz, T., and Gamboa, H. (2020). SoftwareX, 11:100456. Elsevier.

58.  SiWformer: Multi-Scale Feature Fusion via Discrete Wavelet Transformand Vision Transformer. Ahmed, M. W., Wu, Y., Almujally, N. A., Alhasson, H. F., Alharbi, S. S., Jalal, A.*, and Liu, H.* (co-first) (2025). Signal, Image and Video Processing. Springer Nature. ISSN: 1863-1711.

59.  Intelligent Human Interaction Recognition with Multi-Modal Feature Extraction and Bidirectional LSTM. Azhar, M. H., Wu, Y., Almujally, N. A., Alharbi S. S., Algarni, A., Jalal, A.*, and Liu, H.* (co-first) (2025). Computer, Materials & Continua. Tech Science Press. ISSN: 1546-2218.

60.  Transformer-Driven Multimodal for Human-Object Detection and Recognition for Intelligent Robotic Surveillance. Ullah, A. A., Wu, Y., Najam S., Almujally, N. A., Jalal, A.*, and Liu, H.* (2025). Computer, Materials & Continua. Tech Science Press. ISSN: 1546-2218.

61.  Novel Quantum-Integrated CNN Model for Improved Human Activity Recognition in Smart Surveillance. Bukht, T. F. N., Wu, Y., Almujally, N. A., AItarbi, S. S., Rahman, H., Jalal, A.*, and Liu, H.* (2025). Computer Modeling in Engineering & Sciences. Tech Science Press. ISSN: 1526-1492.

62.  Machine Learning-Assisted Parametric Analysis and Multi-Criteria Optimization of Building Performance: A Case Study on Indoor Environmental Quality and Energy Efficiency. Liu, H.*, Wu, Y., Xue, T., Du, Zhe., Xu, J.*, Jiang, T.* (2025). Energy Conversion and Management. Elsevier. ISSN: 0196-8904.

[Conference] ( = Best Paper Award / Best Student Paper Award;   = Best Paper Finalist)

1.  The Bigger the Better? Towards EMG-Based Single-Trial Action Unit Recognition of Subtle Expressions. Küster, D., Rammohan, R. A., Liu, H., Schultz, T., and Koschke, R. (2025). In BIOSTEC 2025 - Proceedings of the 18th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 1: BIODEVICES, pages 100-110. INSTICC, SciTePress.

2.  A Wearable Real-Time Human Activity Recognition System using Biosensors Integrated into a Knee Bandage. Liu, H. and Schultz, T. (2019). In BIOSTEC 2019 - Proceedings of the 12th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 1: BIODEVICES, pages 47–55. INSTICC, SciTePress.

3. Merged Pitch Histogram and Pitch-Duration Histogram. Liu, H., Xue, T., and Schultz, T. (2022). In SIGMAP 2022 - Proceedings of the 19th International Conference on Signal Processing and Multimedia Applications, pages 32-39. INSTICC, SciTePress.

4.  Interpretable High-Level Features for Human Activity Recognition. Hartmann, Y., Liu, H., Lahrberg, S., and Schultz, T. (2022). In BIOSTEC 2022 - Proceedings of the 15th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 4: BIOSIGNALS, pages 40-49. INSTICC, SciTePress.

5. Longitudinal Data Acquisition for AI Services in Long-Term Care Facilities for Older Adults. Paul, R. E., Kock, P., Hartmann, Y., Ball, E., Seibert, K., Liu, H., and Schultz, T. (2025). In BIOSTEC 2025 - Proceedings of the 18th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 2: HEALTHINF, pages 1099-1110. INSTICC, SciTePress.

6. LSTM-MorA: Melody-Accompaniment Classification of MIDI Tracks. Liu, H.*, Flaack, L., Zhang, S., and Schultz, T. (2024). In ICANN 2024 - 33rd International Conference on Artificial Neural Networks, pages 443-485. Springer, Cham.

7. Examining the Effects of Human-Likeness of Avatars on Emotion Perception and Emotion Elicitation. Zhang, S., Faruk, O., Porzel, R., Küster, D., Schultz, T., and Liu, H. (2024). In ABC 2024 - 6th International Conference on Activity and Behavior Computing, pages 1-12. IEEE.

8. Comfort Assessment Method of EEG-Based Exoskeleton Walking-Assistive Device. Zhou, C., Wang, H., Li, K., Liu, H., and Ye, X. (2024). In BIOSTEC 2024 - Proceedings of the 17th International Joint Conference on Biomedical Engineering Systems and Technologies - BIOSIGNALS, pages 675-682. INSTICC, SciTePress.

9. Can Electromyography Alone Reveal Facial Action Units? A Pilot EMG-Based Action Unit Recognition Study with Real-Time Validation. Veldanda, A., Liu, H., Koschke, R., Schultz, T., and Küster, D. (2024). In BIOSTEC 2024 - Proceedings of the 17th International Joint Conference on Biomedical Engineering Systems and Technologies - BIODEVICES, pages 142–151. INSTICC, SciTePress.

10. Really Can't Hold on Anymore? Physiological Indicators Versus Self-Reported Motivation Drop During Jogging. Zhang, S., Kolensnikov, S., Rennspieß, T., Porzel, R., Schultz, T., and Liu, H. (2024). In BIOSTEC 2024 - Proceedings of the 17th International Joint Conference on Biomedical Engineering Systems and Technologies - BIOSIGNALS, pages 821-831. INSTICC, SciTePress.

11. Associating Endpoint Accuracy and Similarity of Muscle Synergies. Cai, L., Yan, S., Ouyang, C., Zhang, T., Zhu, J., Chen, L.*, and Liu, H.* (2024). In BIOSTEC 2024 - Proceedings of the 17th International Joint Conference on Biomedical Engineering Systems and Technologies - BIOSIGNALS, pages 683-694. INSTICC, SciTePress.

12. Integrated Driver Pose Estimation for Autonomous Driving. Cao, X., Hu, W., and Liu, H. (2024). In BIOSTEC 2024 - Proceedings of the 17th International Joint Conference on Biomedical Engineering Systems and Technologies - BIOSIGNALS, pages 695-702. INSTICC, SciTePress.

13. On a Real Real-Time Wearable Human Activity Recognition System. Liu, H., Xue, T., and Schultz, T. (2023). In BIOSTEC 2023 - Proceedings of the 16th International Joint Conference on Biomedical Engineering Systems and Technologies - WHC, pages 711-720. INSTICC, SciTePress.

14. Interactive and Interpretable Online Human Activity Recognition. Hartmann, Y., Liu, H., and Schultz, T. (2022). In PERCOM 2022 - 20th IEEE International Conference on Pervasive Computing and Communications Workshops and other Affiliated Events, pages 109–111. IEEE.

15. A Practical Wearable Sensor-Based Human Activity Recognition Research Pipeline. Liu, H., Hartmann, Y., and Schultz, T. (2022). In BIOSTEC 2022 - Proceedings of the 15th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 5: HEALTHINF, pages 851-860. INSTICC, SciTePress.

16. How Long Are Various Types of Daily Activities? Statistical Analysis of a Multimodal Wearable Sensor-Based Human Activity Dataset. Liu, H., and Schultz, T. (2022). In BIOSTEC 2022 - Proceedings of the 15th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 5: HEALTHINF, pages 684-692. INSTICC, SciTePress.

17. Hidden Markov Model and Its Application in Human Activity Recognition and Fall Detection: A Review. Xue, T., and Liu, H. (2022). Communications, Signal Processing, and Systems. Springer, Singapore.

18. Motion Units: Generalized Sequence Modeling of Human Activities for Sensor-Based Activity Recognition. Liu, H., Hartmann, Y., and Schultz, T. (2021). In EUSIPCO 2021 - 29th European Signal Processing Conference. IEEE.

19. Feature Space Reduction for Human Activity Recognition Based on Multi-Channel Biosignals. Hartmann, Y., Liu, H., and Schultz, T. (2021). In BIOSTEC 2021 - Proceedings of the 14th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 4: BIOSIGNALS, pages 215-222. INSTICC, SciTePress.

20. Feature Space Reduction for Multimodal Human Activity Recognition. Hartmann, Y., Liu, H., and Schultz, T. (2020). In BIOSTEC 2020 - Proceedings of the 13th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 4: BIOSIGNALS, pages 135–140. INSTICC, SciTePress.

21. ASK: A Framework for Data Acquisition and Activity Recognition. Liu, H. and Schultz, T. (2018). In BIOSTEC 2018 - Proceedings of the 11th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 3: BIOSIGNALS, pages 262–268. INSTICC, SciTePress.

22. Bremen Big Data Challenge 2017: Predicting University Cafeteria Load. Weiner, J., Diener, L., Stelter, S., Externest, E., Kühl, S., Herff, C., Putze, F., Schulze, T., Salous, M., Liu, H., Küster, D., and Schultz, T. (2017). KI 2017: Advances in Artificial Intelligence. Springer, Cham.

23. Capacity of Cooperative Ad Hoc Networks with Heterogeneous Traffic Patterns. Liu, H. and Wang, X. (2011). In ICC 2011 - IEEE International Conference on Communications, pages 1–5. IEEE.

24.  A Review of Wearable Detectors for Toxic Environments: Devices, Mechanisms, Integration, and Application Scenarios. Mweetwa, P., Chorouk, E., Liu, H.*, Wu, Y., Zhao, X., Xu, Y., and Yan, X. (2025). Taihu Forum on New Power Systems.

25.  Real-Time Fault Detection in Power Systems Using Custom Anomaly Detection. Li, Y., Liu, H.*, Kogoya, K., Hossain, J., Awasthi, L., Shi, J., Qin, C., Wu, Y., and Hu, B. (2025). Taihu Forum on New Power Systems.

26.  Signal-Driven Fault Detection in Electrical Systems via Adaptive Machine Learning. Li, Y., Liu, H.*, Kogoya, K., Hossain, J., Awasthi, L., Shi, J., Qin, C., Wu, Y., and Hu, B. (2025). Taihu Forum on New Power Systems.

27.  Fault Detection in Power Systems Using Convolutional Neural Networks: A Review of Voltage and Current Data Visualization Techniques. Hossain, J., Islam, T., Liu, H.*, Shi, J., Wu, Y., Qin, C., and Hu, B. (2025). Taihu Forum on New Power Systems.

28.  Time Series vs. Statistial Methods for Small Current Fault Detection: A Comparative Review of Accuracy and Efficiency. Danso, E. O. A., Kawushini, R. P. R., Cabrel, T. P. U., Liu, H.*, Qin, C., Shi, J., Wu, Y., and Hu, B. (2025). Taihu Forum on New Power Systems.

29.  Exploring Time-Series Machine Learning for Voltage Prediction in Air Conditioning Systems. Alam, M. N., Liu, H.*, Hossain, J., Markos, T. E., Shi, J., and Wu, Y. (2025). Taihu Forum on New Power Systems.

30.  A Review on Wearable Proximity Sensing Technologies for Live Electrical Object Detection. Khalil, B., Abraham, M., Liu, H.*, Wu, Y., Zhao, X., Xu, Y., and Yan, X. (2025). Taihu Forum on New Power Systems.

31.  A Hierarchical Model for Digital Twin Enabled Human-Robot Collaboration in Industrial Assembly. Xia, G., Ghrairi, Z., Heuermann, A., Thoben, K-D., Liu, W., Wu, Y., and Liu, H. (2026). International Conference on Digital Twins and Applications (DTA APAC 2026).

32.  Anomaly Discrimination Technique Combining Small Sample Reliability Improvement and Combination Strategy Optimization. Liu, H.*, Liu, W., Zhang, S., Wu, Y., Shi, J., Li, H., Dai, Q., Wang, K. (2026). International Conference on Digital Twins and Applications (DTA APAC 2026).

33.  An Improved Defect Detection System for Substation Equipment Based on Lightweight YOLOv5. Liu, W., Zhang, S., Wu, Y., Shi, J., li, H., Dai, Q., Wang, K., Liu, H.* (2026). International Conference on Digital Twins and Applications (DTA APAC 2026).

34.  A Lightweight Deep Learning Approach for Smooth Luffa Leaf Disease Classification Using ROI. Morshed, M.N., Islam, M. M., Himel, G. M. S., Liu, H., Islam, M. S. (2026). In ICCIT 2026 - 28th International Conference on Computer and Information Technology, IEEE.

Journals

    Editorial Board

        - Regenerative Medicine Reports

        - Engineering Research Express

        - Frontiers in Big Data

        - Frontiers in Artificial Intelligence

    Editor

        - Frontiers in Behavioral Neuroscience

        - Frontiers in Immunology

        - Frontiers in Bioengineering and Biotechnology

        - Frontiers in Endocrinology

    Guest Editor

        - Biosensors: Innovative Technologies of Acquiring, Processing, Modeling, or Utilizing Biomedical and Physiological Signals from Biosensing

        - Biosensors / Sensors: Sensors for Human Activity Recognition: 3^rd Edition

        - Sensors: Electroencephalogram/Electromyogram-Based Sensing Technologies for Biomedical Applications: Challenges and Possible Application

        - Sensors: Sensors for Human Activity Recognition: 2^nd Edition

        - Sensors: Sensors for Human Activity Recognition: 1^st Edition

    Reviewer

        - For 43 international journals, including NC, IEEE Sens., BSPC, GSIS, PMEA, IF, Foods, Front. and Plant Sci.

        - IOP Trusted Reviewer in recognition of an exceptionally high level of peer review competency

        - 2023 Outstanding Reviewer Award of Sensors

Conferences

    General Chair (GC)

        • AIRSA 2026 – 2^nd International Confer ence on Artificial Intelligence and Remote Sensing Applications, Chang

    General Co-Chair (Co-Chair)

        • IS-ALL 2025 – International Symposium on Artificial Intelligence Innovations, Guiyang

        • AIRSA 2025 – International Confer ence on Artificial Intelligence and Remote Sensing Applications, Changsha

        • IS-ALL 2026 – 2^nd International Symposium on Artificial Intelligence Innovations, Guiyan

    Executive Chair (EC)

        • AIM 2025 – International Symposium on AI in Medicine, Nanjing

    Technical Program Chair (TPC)

        • ArtInHCI 2025 – 3^rd International Conference on Artificial Intelligence and Human-Computer Interaction, Nanning

    Program Co-Chair (Co-PC)

        • BIOSIGNALS 2024 – 17^th International Conference on Bio-Inspired Systems and Signal Processing, Rome, Itaty

        • BIOSIGNALS 2026 – 19^th International Conference on Bio-Inspired Systems and Signal Processing, Marbella, Spain

    Technical Program Co-Chair (Co-TPC)

        • ArtInHCI 2024 – 2^nd International Conference on Artificial Intelligence and Human-Computer Interaction, Kunming

    Area Chair (AC)

        • ICANN 2024 – 33^rd International Conference on Artificial Neural Networks, Lugano, Switzerland

        • CEII 2024 – 7^th Asia Conference on Cognitive Engineering and Intelligent Interaction, Singapore

    Publicity Chair

        • ABC2025 – 7^th International Conference on Activity and Behavior Computing, Abu Dhabi, UAE

        • AIGC 2024 – 2^nd International Conference on AI-generated Content, Beijing

        • ICCI 2025 (in prep.) – International Conference on AI-generated Content, Hongkong, Chin

    Doctoral Consortium Co-Chair

        • BIOSTEC 2025 – 18^th International Joint Conference on Biomedical Engineering Systems and Technologies, Porto, Portugal

    Session Chair

        • HEALTHINF 2022 – 15^th International Conference on Health Informatics, Vienna, Austria

        • SIGMAP 2022 – 19^th International Conference on Signal Processing and Multimedia Applications, Lisbon, Portugal

        • BIOSTEC 2023 – 16^th International Joint Conference on Biomedical Engineering Systems and Technologies, Lisbon, Portugal

        • HEALTHINF 2025 – 18^th International Conference on Health Informatics, Porto, Portugal

    Keynote Speaker

        • 4^th International Symposium on Clinical Medicine and Intelligent DevicesHeidelberg, Germany 2025: Wearable Medical AI

        • 3^rd International Conference on Artificial Intelligence and Human-Computer Interaction, Nanning, China 2025: Human-Triggered Machine Learning (HTML)

        • 3^rd Civil Aviation Flight and Operation Technology Forum, Chengdu, China 2025: Human Factors in Civil Aviation Security

    Invited Speaker

        • Verein der CDHAW-Absolventen und Mitglieder der Tongji-Universität, Düsseldorf, Germany 2018: Academics and Art

        • NOVA Universidade de Lisboa, Lisbon, Portugal 2018: Biosignals and Cognitive Systems

        • Bremen.AI Exhibition Symposium 2019: Real-time Recognition and Mixed Reality

        • Lecture Series of the 3rd European University Theater Festival, Frankfurt, Germany 2019: From Script to Stage

        • 12th International Joint Conference on Biomedical Engineering Systems and Technologies, Prague, Czech 2019: From Offline towards Real-Time (Tutorial)

        • MindDay Symposium on Cognitive Science, Bremen, Germany 2021: Smart Knee Bandage

        • Karlsruher Institut für Technologie - KD²school Adaptive Systems Talks, Karlsruhe, Germany 2022: Smart Knee Bandage 

        • Lecture Series of the 6th European University Theater Festival, Frankfurt, Germany 2022:The Stage Performance Art of Local Chinese Operas and Quyi

        • Zhejiang Lab for Regenerative Medicine, Vision and Brain Health, Wenzhou, China 2024: Multimodal Wearable Biosignal Sensors

        • 9^th Bremen Big Data Challenge (BBDC 2024) Award Ceremony Summit, Bremen, Germany 2024: What Else Can Physiological Signals Bring to Smart Life?

        • Huadian New Power System Technology Innovation Forum, Nanjing, China 2025: Biosignals for the Safety of Power Operation and Mintenance Personnel

        • NOVA Universidade de Lisboa, Lisbon, Portugal: HTML: Human-Triggered Machine Learning

    Reviewer

        • For various conferences, including IEEE BSN, BHI; ACM ICMI, ISWC, AUTOMOTIVEUI; ITP

Big Data Challenge Organizer

    4^th BBDC 2019

        • Big data acquisition, processing, and provision (individually)

        • Over 60 teams from north German universities participated in the final round

    9^th BBDC 2024

        • Main responsible orgnizer for Basic Track