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, Quyi 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.

6. Proceedings of the 19th International Joint Conference on Biomedical Engineering Systems and Technologies – Volume 1: BIOSIGNALS. Bahnemann, J., Fudickar, S., Mercaldo F., Solé-Casals, J., Liu, H., Kaldoudi, E., and Gamboa, H. （2026） INSTICC.

7. Proceedings of the 19th International Joint Conference on Biomedical Engineering Systems and Technologies – Volume 2: BIODEVICES, BIOIMAGING and BIOINFORMATICS. Bahnemann, J., Fudickar, S., Mercaldo F., Solé-Casals, J., Liu, H., Kaldoudi, E., and Gamboa, H. (2026). INSTICC.

8. Proceedings of the 19th International Joint Conference on Biomedical Engineering Systems and Technologies – Volume 3: HEALTHINF. Bahnemann, J., Fudickar, S., Mercaldo F., Solé-Casals, J., Liu, H., Kaldoudi, E., and Gamboa, H. (2026). INSTICC.

9. Proceedings of the 19th International Joint Conference on Biomedical Engineering Systems and Technologies – Volume 4: HEALTHINF. Bahnemann, J., Fudickar, S., Mercaldo F., Solé-Casals, J., Liu, H., Kaldoudi, E., and Gamboa, H. (2026). INSTICC.

10.  Biomedical Engineering Systems and Technologies. Bahnemann, J., Fudickar, S., Mercaldo F., Solé-Casals, J., Liu, H., Kaldoudi, E., and Gamboa, H. (2026). Springer Nature Switzerland.

11.  Sensors for Human Activity Recognition III. Liu, H., Gamboa, H., and Schultz, T. (2026). MDPI.

[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.  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. ISSN: 2352-7110.

10.  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.

11.  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.

12. SleepCode: A Novel Attention-Driven Multimodal Framework for Sleep Staging and Obstructive Apnea Screening. Kamal, A., Wu, Y., Aljuaid, H., Najam, S., Alnowaiser, K., Jalal, A.*, and Liu, H.* (2026). IEEE Transaction on Consumer Electronics. ISSN: 0098-3063.

13. A Unified Deep Learning-Driven UAV Vehicle Detection Using Robust Feature Extraction for Intelligent Traffic Monitoring System. Ghulam, M., Wu Y., Almujally, N. A., Alnowaiser, K. Ullah, A., Jalal, A.*, and Liu, H.* (2026). Kuwait Journal of Science. Elsevier. ISSN: 2307-4108.

14. Toward Intelligent Rehabilitation: Multimodal Human Pose Modeling with Parametric Meshes and Graph-Based Temporal Reasoning Kamal1, A., Wu, Y., Najam, S., Almujally, N. A., Jalal, A.*, and Liu, H.* (2026). Digital Health. Sage Journals. ISSN: 2055-2076.

15. Multimodal Healthcare System for Human Activity Recognition using Multiple Features and Advanced Ensemble Classifier. Nazar1, F., Wu, Y., Aljuaid, H., Jalal, A.*, and Liu, H.* (co-first) (2026). Digital Health. Sage Journals. ISSN: 2055-2076.

16. FALCON-HiMRAN: A Dual-Stage RGB-D Sensor-Based Scene Classification Framework with Cross-modal Fusion and Graph Reasoning. Almujally, N. A., Wu, T., Ahmed, M. W., Jalal, A.*, and Liu, H.* (2026). Sensors and Materials. MYU K.K. ISSN: 0914-4935.

17. Group Activity Recognition in Crowded Scenes Using Multi-Stage Feature Optimization and ST-GCN-LSTM Networks. Alnusayri, M., Xue, T., Kamal, S., Almujally, N. A., Alnowaiser, K., Jalal, A.*, and Liu, H.* (2026). Computer, Materials & Continua. Tech Science Press. ISSN: 1546-2218.

18. Scalable Video Sensors for Understanding Multiperson Sports Behavior Recognition in Dynamic Scenes. Kamal, S., Wu, Y., Almujally N. A., Jalal, A.*, and Liu, H.* (2026). Sensors and Materials. MYU K.K. ISSN: 0914-4935.

19. A Novel Approach for Fair Incentive Social Physical Data Based on Blockchain-Federated Learning. Mohamed, H. G., Tran-Huy, H.*, Hoang-Thu, T., Qaddara, I., Choi, B. J.*, Alshehri, A. H., Ahad, I., and Liu, H.* (2026). Frontiers in Physics. ISSN: 2296-424X.

20. A Multimodal Deep Learning Approach for Recognizing Individual Actions and Group Interactions from UAV-Based Aerial Monitoring. Zahra1, I., Wu, Y., Alsolai, H., Alabdullah, B., Alhayan, F., Jalal, A.*, and Liu, H.* (2026). Kuwait Journal of Science. Elsevier. ISSN: 2307-4108.

21. Multimodal Neural Network Framework for Individual and Social Activity Recognition in UAV Surveillance. Zahra, I., Alsolai, H., Alabdullah, B., Alhayan, F., Jalal, A.*, and Liu, H.* (2026). IEEE Access.

22. 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.

23. 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.

24. 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.

25. 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.

26. 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.

27. 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. ISSN: 2296-4185.

28. 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.

29. 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.

30. 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.

31. 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.

32. 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.

33. 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.

34. 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.

35. 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.

36. 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.

37. 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.

38. 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.

39. 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.

40. 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)

41. 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.

42. 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.

43. 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.

44. 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.

45. 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.

46. 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.

47. 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.

48. 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.

49. 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.

50. 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.

51. 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.

52. 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.

53. 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.

54. 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.

55. 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.

56. 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.

57. 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.

58. 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.

59. 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.

60. 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. Tech Science Press. ISSN: 1546-2218.

61. 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. ISSN: 2296-4185.

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

63. 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. ISSN: 1662-5218.

64. 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.

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

66. 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.

67. 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. Elsevier. ISSN: 1746-8094.

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

69. 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. MDPI. ISSN: 2079-6374.

70. 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.

71. 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. Elsevier.

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

73.  Lightweight Lifecare Remote Monitoring System for Human Behavior Interaction Using Embedded HMM. Bukht, T. F. N., Wu, Y., Alabdullah, B., Alnowaiser, K., Jalal, A.*, and Liu, H.* (2026). Sensors and Materials, MYU K.K. ISSN: 0914-4935.

74.  Human Monitoring in Smart Homes for Digital Health: Enhancing Healthcare through Action Recognition. Bukht T. F. N, Wu, Y., Alnowaiser, K., Almujally, N. A., Liu, H.* (2026). Digital Health. Sage Journals. ISSN: 2055-2076.

75.  Deep Deterministic Policy Gradient Algorithm for Efficient Social Physical Data Optimization in Intelligent Transportation System Based on IRS Deep Reinforcement Learning. Zhao, W., Faizal, D., Hinov, N., Abdelhaq, M., Choi, B. J., and Liu, H.* (2026). Frontiers in Physics. ISSN: 2296-424X.

76.  Unsupervised Diffusion-trajectory Segmentation and Multiregion Fusion for Understanding RGB–thermal Scene. Ahmed, M. W., Xue, T., Almujally, N. A., Jalal, A.*, and Liu, H.* (2026). Sensors and Materials, MYU K.K. ISSN: 0914-4935.

[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. Influence of Multi-Wavelength Sensor Array Design on Signal Stability and Application in Blood Pressure Detection. Zhou, C., Zheng, Y., Yu, L., Hu, Y., Wang, H., Liu, H., Ye, X. (2026). In Proceedings of the 19th International Joint Conference on Biomedical Engineering Systems and Technologies – Volume 4: BIOSIGNALS. INSTICC, SciTePress.

6. 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). In DTA APAC 2026 - IET International Conference on Digital Twins and Applications. IET Conference Proceedings, 2026:1, pages 1-6. IET.

7. 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). In DTA APAC 2026 - IET International Conference on Digital Twins and Applications. IET Conference Proceedings, 2026:1. IET.

8. 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). In DTA APAC 2026 - IET International Conference on Digital Twins and Applications. IET Conference Proceedings, 2026:1. IET.

9. 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.

10. 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. INSTICC, SciTePress.

11. 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. Springer, Cham.

12. 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. IEEE.

13. 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. INSTICC, SciTePress.

14. 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. INSTICC, SciTePress.

15. 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. INSTICC, SciTePress.

16. 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. INSTICC, SciTePress.

17. 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. INSTICC, SciTePress.

18. 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. INSTICC, SciTePress.

19. 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. IEEE.

20. 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. INSTICC, SciTePress.

21. 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. INSTICC, SciTePress.

22. 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.

23. 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.

24. 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. INSTICC, SciTePress.

25. 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. INSTICC, SciTePress.

26. 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. INSTICC, SciTePress.

27. 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.

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

29.  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. (2026). In PSGEC 2026 - 6th Power System and Green Energy Conference. IEEE.

30.  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. (2026). In PSGEC 2026 - 6th Power System and Green Energy Conference. IEEE.

31.  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. (2026). In PSGEC 2026 - 6th Power System and Green Energy Conference. IEEE.

32.  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. (2026). In PSGEC 2026 - 6th Power System and Green Energy Conference. IEEE.

33.  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. (2026). In PSGEC 2026 - 6th Power System and Green Energy Conference. IEEE.

34.  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. (2026). In PSGEC 2026 - 6th Power System and Green Energy Conference. IEEE.

35.  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. (2026). In PSGEC 2026 - 6th Power System and Green Energy Conference. IEEE.

[Journals]

Editor-in-Chief

- Journal of Engineering Research and Sciences

Editorial Board

- Regenerative Medicine Reports

- Engineering Research Express

- Frontiers in Big Data

- Frontiers in Artificial Intelligence

- AI+

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 for Human Activity Recognition: 3rd Edition

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

- SENSORS: Advances in EEG/EMG-Based Sensing Technologies for Biomedical Applications: Challenges and Opportunities

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

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

- SENSORS: Sensors for Human Activity Recognition: 3rd Edition

- SENSORS: Sensors for Human Activity Recognition: 4th Edition

Reviewer

- For over 50 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

- SENSORS 2023 Outstanding Reviewer Award

[Conferences]

General Chair/Co-Chair (GC/Co-GC)

- 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 – 2nd International Symposium on Artificial Intelligence Innovations, Sanya

- AIRSA 2026 – 2nd International Confer ence on Artificial Intelligence and Remote Sensing Applications, Zhengzhou

- FHCI 2026 – Future of Human-Computer Interaction Conference, Berlin, Germany

- LHMM 2026 – 5th International Conference on Life, Health and Modern Medicine, Seoul, South Korea

- IAIC 2026 – International Artificial Intelligence Conference, Singapore (Host)

- EPES 2026 – 6th International Conference on Frontiers of Electrical Power & Energy Systems, Hohhot

- MedBioAI 2026 – International Conference on Artificial Intelligence in Medicine and Bioinformatics, Nanjing

- ICCIA 2026 – 11th International Conference on Computational Intelligence and Application, Qingdao

Executive Chair (EC)

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

- 2026 Conference on the Development of Artificial Intelligence, AI Robotics and Intelligent Sensing Industry, Hangzhou

Technical Program Chair/Co-Chair (TPC/Co-TPC)

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

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

- WCBE 2026 – 3rd World Conference on Biometerials and Engineering, Nanchang

- ArtInHCI 2026 – 4th International Conference on Artificial Intelligence and Human-Computer Interaction, Wuhan

- URSAI 2026 – International Conference on UAV Remote Sensing and Artificial Intelligence, Beijing

Program Co-Chair (Co-PC)

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

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

Area Chair (AC)

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

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

- ICANN 2026 – 35th International Conference on Artificial Neural Networks, Padua, Italy

Publicity Chair

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

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

Doctoral Consortium Co-Chair

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

Session Chair

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

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

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

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

Keynote Speaker

- CMID 2025 – 4th International Symposium on Clinical Medicine and Intelligent Devices, Heidelberg, Germany, 2025: Wearable Medical AI

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

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

- LHMM 2026 – 5th International Conference on Life, Health and Modern Medicine, Seoul, South Korea, 2026: Human-Centric Medical AI Practice

- WCBE 2026 – 3rd World Conference on Biometerials and Engineering, Nanchang, 2026: Artificial Intelligence on Multimodal Wearable Biomedical Sensors

- 2026 Conference on the Development of Artificial Intelligence, AI Robotics and Intelligent Sensing Industry, Hangzhou, 2026: Human Activity Research

- DMI 2026 – 5th International Conference on Digitalization and Management Innovation, Xi'an, 2026: HTML: Human-Triggered Machine Learning

- IEEE EEE 2026 – 3rd International Conference on Energy and Electrical Engineering, Nanchang, 2026: OA and Powerful Time-series Toolkits with Applications in EE

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

- 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

- 9th 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, 2025: HTML: Human-Triggered Machine Learning

- Chinese Arts-Medicine Association, Beijing, China, 2026: Non-invasive EMG Detection Research and AI Achievements in Art Acoustics

- Kyungpook National University, Seoul, South Korea, 2026: Human-Triggered Machine Learning

- Nanjing Children's Hospital, Nanjing Medical University, Nanjing, China, 2026: Wearable Multi-Modality in Medical Sensing

Reviewer

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

[Big Data Challenge Organizer]

4th BBDC 2019

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

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

9th BBDC 2024

- Main responsible orgnizer for Basic Track