Ir Dr. S.K. Lai
BEng, PhD, RPE, CEng, CPEng, NER, MHKIE, MIMechE, MIEAust
Associate Professor
Department of Civil and Environmental Engineering
The Hong Kong Polytechnic University
Email: sk.lai@polyu.edu.hk
Tel: (852) 2766 6060

Vacancies

• Hong Kong PhD Fellowship

The Hong Kong Polytechnic University invites expressions of interest from graduates with evidence of academic excellence and research ability. The scheme aims to recruit outstanding graduates, irrespective of country of origin, prior work experience and ethnic background, and will provide a 3-year tuition scholarship, a monthly stipend of HK$27,100 and Conference and Research related travel allowance of HK$13,600 per year for awardees.

• University Ph.D. Studentship

We are looking for students intending to pursue Ph.D degree at PolyU. The applicants should have satisfactory TOEFL or IELTS scores, preferably with a master degree in civil or mechanical engineering or other related fields. A 3-year studentship will be offered to successful candidates.

• Research Assistant/Associate/Fellow

Research Assistant/Associate/Fellow positions are now available. Successful applicants will work on the following topics: (1) Energy Harvesting, (2) Structural Dynamics, (3) Topology Optimization, and (4) Acoustic Metamaterials. Applicants are expected to have a good Bachelor/Master/PhD degree in structural engineering, mechanical engineering, engineering mechanics or other related areas.

Academic Qualifications

• PhD Degree, City University of Hong Kong
• BEng Degree (First Class Honours), City University of Hong Kong

Professional Qualifications

• Registered Professional Engineer (Fire Discipline), Hong Kong
• Registered Professional Engineer (Mechanical Discipline), Hong Kong
• Registered Professional Engineer (Mechanical Discipline), National Engineering Register, Australia
• Chartered Engineer, Engineering Council (UK)
• Chartered Professional Engineer, Institution of Engineers Australia
• Member, Hong Kong Institution of Engineers (Fire Discipline, Mechanical Discipline)
• Member, Institution of Mechanical Engineers
• Member, Institution of Engineers Australia

Professional Services

• Committee Member, Fire Division, The Hong Kong Institution of Engineers
• Associate Editor, Journal of Vibration & Engineering Technologies 
• Associate Editor, International Journal of Dynamics and Control 

Selected Research and Teaching Projects

• PI: Empowering a multifunctional acoustically driven TENG-based particulate capturing system for a healthy living environment, General Research Fund, Research Grants Council of Hong Kong, 1/2025–12/2027.
• PI: Development of a new inerter-based rail damper to mitigate railway-induced ground-borne noise by a physics-informed deep learning framework, MTR Research Funding Scheme, 7/2024–12/2026.
• PI: Dynamic analysis of a physics-informed neural network-based tri-hybrid gentle wind-driven energy harvesting technique, National Natural Science Foundation of China (General Program), 1/2024–12/2027.
• PI: Developing an innovative space-coiling metasurface barrier to promote a sustainable and healthy urban environment: Energy harvesting and noise control, FCE Young Researcher Collaborative Research Fund, The Hong Kong Polytechnic University, 5/2024–4/2026.
• Co-PI: INTACT: Intelligent tropical-storm-resilient system for coastal cities, Theme-based Research Scheme, Research Grants Council of Hong Kong, 1/2024–12/2028.
• PI: Engineering an integrated wireless sensing system for high-speed trains: System design and field test, Strategic Importance Scheme, The Hong Kong Polytechnic University, 4/2022–6/2024.
• Co-I: A new membrane-flood gate system for extreme weather hazardous mitigations for use in Hong Kong and worldwide, Innovation and Technology Fund, 2021-2022.
• PI: Exploring CNT-based thermo-acoustic agglomeration for better indoor air quality, General Research Fund, Research Grants Council of Hong Kong, 2020–2023.
• Co-PI: Enhancing safety, punctuality and ride comfort of railway transportation: From local metro system to global high-speed rail network, Research Impact Fund, Research Grants Council of Hong Kong, 2019–2023.
• PI: Smart noise barriers/enclosures for dual active and passive control of construction noise, Environment and Conservation Fund, 2018–2020.
• PI: On nonlinear dynamic analysis of piezoelectric functionally graded carbon nanotube-reinforced composite material structures, National Natural Science Foundation of China (Young Scientists Fund), 2017–2019.
• PI: Exploiting mechanical nonlinearities in piezoelectric vibration energy harvesting via thermo-acoustic waves for broadband transduction, Early Career Scheme, Research Grants Council of Hong Kong, 2017–2019.
• PI: Beamforming system with acoustical array and its accessories for the noise source mapping of various modes of transportation, Large Equipment Fund for Teaching, The Hong Kong Polytechnic University, 2016.
• PI: Fabrication of thermo-acoustic wave generator using suspended carbon nanotube thin-films, Start-up Fund, The Hong Kong Polytechnic University, 2015–2018.

Teaching Experience

• Noise Pollution Control (MSc Subject)
• Statutory Framework for Construction Practice(MSc Subject)
• Air and Noise Pollution Control (Undergraduate Subject)
• Air and Noise Pollution Studies (Undergraduate Subject)
• MSc Dissertation

Selected Journal Publications (*Corresponding author)

• C.N. Liu, S.K. Lai^*, Y.Q. Ni, and L. Chen, Dynamic modelling and analysis of a physics-driven strategy for vibration control of railway vehicles, Vehicle System Dynamics, Accepted, 2024.
• C. Wang, H. Chai, G. Li, W. Wang, R. Tian, G.L. Wen, C.H. Wang, and S.K. Lai^*, Boosting biomechanical and wave energy harvesting efficiency through a novel triple hybridization of piezoelectric, electromagnetic, and triboelectric generators, Applied Energy, Accepted, 2024.
• J.M. Wang, S.K. Lai^*, C. Wang, Y.T. Zhang, and Z.L. Chen, On the role of sliding friction effect on nonlinear tri-hybrid vibration-based energy harvesting, Applied Mathematics and Mechanics (English Edition), Accepted, 2024.
• Z.L. Chen, S.K. Lai^* and Z.C. Yang, AT-PINN: Advanced time-marching physics-informed neural network for structural vibration analysis, Thin-Walled Structures, 196, 111423, 2024.
• Z.C. Yang, S.K. Lai^*, J. Yang, A. Liu, and J. Fu, Coupled dynamic instability of graphene platelet-reinforced dielectric porous arches under electromechanical loading, Thin-Walled Structures, 197, 111534, 2024.
• Z.W. Song, S.K. Lai^*, B.S. Wu, A new MIB-based time integration method for transient heat conduction analysis of discrete and continuous systems, International Journal of Heat and Mass Transfer, 222, 125153, 2024.
• D.X. Cao, S.S. Li, X.Y. Guo^*, X.M. Chen and S.K. Lai^*, Buckling-driven piezoelectric defect-induced energy localization and harvesting using a Rubik’s cube-inspired phononic crystal structure, Smart Materials and Structures, 33, 035036, 2024.
• M. Guzari^*, Q. Zhang, E. King, L.H. Tong, and S.K. Lai, Valley edge states with opposite chirality in temperature dependent acoustic media, Journal of Physics D: Applied Physics, 57, 345303, 2024.
• X.C. Liu, H. Ding^*, X.F. Geng, K.X. We, S.K. Lai and L.Q. Chen, A magnetic nonlinear energy sink with quasi-zero stiffness characteristics, Nonlinear Dynamics, 112, 5895–5918, 2024.
• Y.T. Zhang, S.K. Lai^* and C.H. Wang, Experimental investigation of two- and three-dimensional graphene-based thermo-acoustic sound generating devices: Analysis of gap separation effect, Composites Part B: Engineering, 266, 110918, 2023.
• Z.W. Song, Y.T. Zhang and S.K. Lai^*, Analytical solutions for buckling analysis of cracked plates under in-plane compressive loads: 2D refined modeling, Structures, 57, 105201, 2023.
• C.Wang, C.X. Wang, Y. Ji, Y. Liu, G. Li, G.L. Wen, Y.Q. Ni and S.K. Lai^*, Boosting output performance of tri-hybrid vibration-based generator via quin-stable nonlinearity and speed amplification, Mechanical Systems and Signal Processing, 204, 110809, 2023.
• C.Wang, Y. Ji, S.K. Lai^*, Y. Liu, Y. Hao, G. Li, C.X. Wang and G.L. Wen, A speed-amplified tri-stable piezoelectric-electromagnetic-triboelectric hybrid energy harvester for low-frequency applications, Nano Energy, 114, 108630, 2023.
• Z.W. Song and S.K. Lai^*, Two-dimensional orthotropic plate problems in a thermal environment: Refined crack modelling, European Journal of Mechanics – A/Solids, 102, 105098, 2023.
• Z.W. Song, S.K. Lai^* and J.G. Dai, Refined models for free vibration analysis of elastic plates with part-through surface cracks, Thin-Walled Structures, 182, 110312, 2023.
• Z.W. Song, S.K. Lai^*, W. Li and S.L. Chan, A series of multi-domain matched interface and boundary algorithms for dynamic and static responses of annular sectorial plates, Thin-walled Structures, 180, 109883, 2022.
• X. Yang, S.K. Lai*, C. Wang, J.M. Wang and H. Ding, On a spring-assisted multi-stable hybrid-integrated vibration energy harvester for ultra-low-frequency excitations, Energy, 252, 124028, 2022.
• D.X. Cao, Y.M. Lu, S.K. Lai, J.J. Mao, X.Y. Gao* and Y.J. Shen, A novel soft encapsulated multi-directional and multi-modal piezoelectric vibration energy harvester, Energy, 254, 124309, 2022. 
• X.Q. Zhao, B.S. Wu, S.K. Lai*, W.J. Liu and H.X. Zhong, Topology optimization of proportionally damped structures under harmonic excitations: Analysis of velocity and acceleration responses, Engineering Structures, 258, 114140, 2022. 
• Z.C. Yang, A.R. Liu, S.K. Lai*, B. Safaei, J. Lv, Y.H. Huang and J.Y. Fu*, Thermally induced instability on asymmetric buckling analysis of pinned-fixed FG-GPLRC arches, Engineering Structures, 250, 113243, 2022. 
• D.X. Cao, J. Wang, X.Y. Cao*, S.K. Lai and Y.J. Shen, Recent development of flow-induced vibration energy harvesting: Principles, structures and nonlinear designs, Applied Mathematics and Mechanics (English Edition), 43, 959–978, 2022.
• Y.T. Zhang, S.K. Lai*, J.C.W. Yu, H. Guo and C.W. Lim, A novel U-shaped acoustic-manipulated design to enhance the performance of low-efficiency filters for sub-micron particles, Powder Technology, 392, 412–423, 2021.
• C. Wang, S.K. Lai*, J.M. Wang, J.J. Feng and Y.Q. Ni, An ultra-low-frequency, broadband and multi-stable tri-hybrid energy harvester for enabling the next-generation sustainable power, Applied Energy, 291, 116825, 2021.
• Y.L. Liu, Z. Liu, S.K. Lai*, L.Z. Luo and J.G. Dai*, Debonding detection in the grouted joints of precast concrete shear walls using impact-echo method, Journal of Nondestructive Evaluation, 40(2), Article 50, 2021.
• Z.C. Yang, D. Wu, J. Yang*, S.K. Lai, J. Lv, A.R. Liu, and J.Y. Fu, Dynamic buckling of rotationally restrained FG porous arches reinforced with graphene nanoplatelets under a uniform step load, Thin-Walled Structures, 166, 108103, 2021.
• X.Q. Zhao, B.S. Wu, S.K. Lai*, Z.G. Li and H.X. Zhong, A PEM-based topology optimization for large-scale structures subjected to stationary random excitations, Engineering Structures, 229, 111613, 2021.
• Z.C. Yang, A.R. Liu, J. Yang, S.K. Lai, J. Lv and J.Y. Fu*, Analytical prediction for nonlinear buckling of elastically-supported FG-GPLRC arches under a central point load, Materials, 14, 2026, 2021.
• D.X. Cao, W. Xia, X.Y. Guo* and S.K. Lai, Modeling and experiment of vibro-impact vibration energy harvester based on a partial interlayer-separated piezoelectric beam, Journal of Intelligent Material Systems and Structures, 32, 817–831, 2021.
• S.K. Lai*, Y.T. Zhang and J.Q. Sun, Application of probabilistic assessment for optimal prediction in active noise control algorithms, Applied Acoustics, 173, 107675, 2021.
• L.H. Zhang, S.K. Lai*, C. Wang and J. Yang, DSC regularized Dirac-delta method for dynamic analysis of FG graphene platelet-reinforced porous beams on elastic foundation under a moving load, Composite Structures, 255, 112865, 2021. 
• J.F. Wang, J.P. Yang, S.K. Lai, W. Zhang*, Stochastic meshless method for nonlinear vibration analyses of composite plates reinforced by carbon fibers, Aerospace Science and Technology, 105, 105919, 2020.
• X. Yang, C. Wang, S.K. Lai*, A magnetic levitation-based tristable hybrid energy harvester for scavenging energy from low-frequency structural vibration, Engineering Structures, 221, 110789, 2020.
• D.X. Cao, X.J. Duan, X.Y. Guo, S.K. Lai, Design and performance enhancement of a force-amplified piezoelectric stack energy harvester under pressure fluctuations in hydraulic pipeline systems, Sensors and Actuators A: Physical, 309, 112031, 2020.
• L.H. Zhang, S.K. Lai* and J. Yang, A DSC regularized Dirac-delta method for flexural vibration of elastically supported FG beams subjected to a moving load, International Journal of Structural Stability and Dynamics, 20(3), 2050039, 2020.
• J.J. Mao, H.M. Lu, W. Zhang* and S.K. Lai, Vibrations of graphene nanoplatelet reinforced functionally gradient piezoelectric composite microplate based on nonlocal theory, Composite Structures, 236, 111813, 2020.
• C. Wang, S.K. Lai*, Z.C. Wang, J.M. Wang, W.Q. Yang and Y.Q. Ni, A low-frequency, broadband and tri-hybrid energy harvester with septuple-stable nonlinearity-enhanced mechanical frequency up-conversion mechanism for powering portable electronics, Nano Energy, 64, 103943, 2019.
• L.H. Tong, Y. Yu, S.K. Lai* and C.W. Lim, Dynamic weakening of sandstone subjected to repetitive impact loading, Rock Mechanics and Rock Engineering, 52, 2197–2206, 2019.
• S.K. Lai*, X. Yang and F.B. Gao, Analysis of large-amplitude oscillations in triple-well non-natural systems, Journal of Computational and Nonlinear Dynamics-Transactions of the ASME, 14, 091002, 2019.
• S.K. Lai*, L.H. Tong and C.W. Lim, On the reflection and diffraction of carbon nanotube array thin film, Wave Motion, 90, 196–204, 2019.
• S.K. Lai*, J. Chui, L.H. Tong, J.Q. Sun, A human-based study of hand-arm vibration exposure limits for construction workers, Journal of Vibration Engineering & Technologies, 7(4), 379-388, 2019.
• S.K. Lai*, X. Yang, C. Wang, and W.J. Liu, An analytical study for nonlinear free and forced vibration of electrostatically actuated MEMS resonators, International Journal of Structural Stability and Dynamics, 19(7), 1950072, 2019.
• C. Li, S.K. Lai*, X. Yang, On the nano-structural dependence of nonlocal dynamics and its relationship to the upper limit of nonlocal scale parameter, Applied Mathematical Modelling, 69, 127–141, 2019.
• S.K. Lai, C. Wang* and L.H. Zhang, A nonlinear multi-stable piezomagnetoelastic harvester array for low-intensity, low-frequency and broadband vibrations, Mechanical Systems and Signal Processing, 122, 87–102, 2019.
• J.W. Yan, S.K. Lai* and L.H. He, Nonlinear dynamic behavior of single-layer graphene under uniformly distributed loads. Composites Part B: Engineering, 165, 473–490, 2019.
• L.H. Tong, S.K. Lai*, J.W. Yan and C. Li, Highly directional acoustic waves generated by a horned parametric acoustic array loudspeakers, Journal of Vibration and Acoustics-Transactions of the ASME, 141, 011012, 2019.
• S.K. Lai* and L.H. Zhang, Thermal effect on vibration and buckling analysis of thin isotropic/orthotropic rectangular plates with crack defects, Engineering Structures, 177, 444-458, 2018.
• L.H. Tong, S.K. Lai*, L.L. Zeng, C.J. Xu, J. Yang, Nonlocal scale effect on Rayleigh wave propagation in porous fluid-saturated materials, International Journal of Mechanical Sciences, 148, 459–466, 2018.
• Z.G. Li, S.K. Lai*, B.S. Wu, A new method for the computation of eigenvector derivatives with distinct and repeated eigenvalues in structural dynamic analysis,  Mechanical Systems and Signal Processing, 107, 78–92, 2018.
• Y.S. Liu, L.H. Tong*, and S.K. Lai, Thermo-acoustics generated by periodically heated thin line array, Journal of Sound and Vibration, 427, 28–40, 2018.
• L.H. Zhang, Y.W. Wang, Y.Q. Ni, S.K. Lai*, Online condition assessment of high-speed trains based on Bayesian forecasting approach and time series analysis, Smart Structures and Systems, 21(5), 705–713, 2018.
• L.H. Tong, Y.S. Liu, D.X. Geng and S.K. Lai*, Nonlinear wave propagation in porous materials based on Biot theory, The Journal of the Acoustical Society of America, 142, 759–770, 2017.
• L.H. Tong*, S.K. Lai, and C.W. Lim, Broadband signal response of thermo-acoustic devices and its applications, The Journal of the Acoustical Society of America, 141, 2430–2439, 2017.

Selected Conference Papers

• Z.L. Chen and S.K. Lai, Vibration analysis based on a novel physics-informed neural network technique, Proceedings of the 3^rd ZHITU Symposium on Advances in Civil Engineering, Tokyo, Japan, 20–22 August 2023.
• J.M. Wang and S.K. Lai, Theoretical analysis of a tri-hybrid multi-stable vibration-based energy harvester with auxetic structures under ultra-low-frequency excitations, Proceedings of the 3^rd International Conference on Mechanics of Advanced Materials and Structures, Texas, US, 9–10 August 2023.
• Y.T. Zhang and S.K. Lai, Manipulation of acoustic waves for air and noise control studies, Proceedings of the 6^th International Conference on Dynamics, Vibration and Control (ICDVC 2022+1), Shanghai, China, 7–9 April 2023. (Invited Talk)
• S.K. Lai, A world of IoT opportunity for smart railway development: Toward a self-powered real-time monitoring system, The Second International Young Scholars Forum on Intelligent Transportation Infrastructure, 20 October 2022 (Invited Talk).
• S.K. Lai, C. Wang, L.H. Zhang and Y.Q. Ni, Realizing a self-powered real-time monitoring system on high-speed trains, Proceedings of Inter-Noise 2021 Congress, Washington DC, US, 1–5 Aug 2021.
• S.K. Lai, Y.T. Zhang, J.C.W. Yu and Y. Li, A new approach for an induced coagulation of particulate matter through thermo-acoustic agglomeration, Proceedings of Inter-Noise 2020 E-Congress, Seoul, Korea, 23–26 Aug 2020.
• S.K. Lai, Y.T. Zhang, J.M. Wang, S.Y. Leu and J.Q. Sun, Investigation of a smart noise barrier for dual active and passive control of construction noise, Proceedings of Inter-Noise 2020 E-Congress, Seoul, Korea, 23–26 Aug 2020.
• C. Wang and S.K. Lai, Exploiting a novel multi-stable strategy for low-frequency and broadband vibration energy harvesting: Experimental Studies, Proceedings of The 2019 Asian Workshop on Theoretical and Applied Mechanics, Hangzhou, China, 24–27 Aug 2019. (Invited Presentation)
• S.K. Lai and Y.T. Zhang, Real-time prediction of noise signals for active control based on Bayesian forecasting and time series analysis, Proceedings of Inter-Noise 2019 Congress, Madrid, Spain, 16–19 Jun 2019.
• C. Wang, X. Yang and S.K. Lai, Nonlinear dynamics and performance enhancement of multi-stable wideband energy harvesting: Theoretical analysis, Proceedings of the 2nd International Conference on Modeling in Mechanics and Materials, Suzhou, China, 29–31 March 2019.
• S.K. Lai and L.H. Zhang, Stability and dynamic analysis of standing vertical plates under thermal effect, Proceedings of ZHITU Symposium on Advances in Civil Engineering, Hangzhou, China, 12–14 Jul 2018.
• S.K. Lai, Y.Q. Ni and L.H. Zhang, A correlation study vibration and noise signals by analyzing its responses for monitoring of high-speed trains, Proceedings of the 11th International Workshop on Structural Health Monitoring, Stanford University, California, US, 12–14 September, 2017.
• S.K. Lai and Y.Q. Ni, Active control for low-frequency noise in high-speed trains by thermo-acoustic waves, Proceedings of Railway Engineering - 2017, Edinburgh, UK, 21-22 June 2017.
• B.S. Wu. S.K. Lai and C.W. Lim, The development and applications of an accurate approximate analytical approach for strongly nonlinear dynamical systems, Proceedings of the 16th Nonlinear Vibration Conference in China, Keynote Paper, Hangzhou, China, 25–27 May 2017.
• L.H. Tong, C.W. Lim, S.K. Lai and Y.C. Li, Carbon nanotube optoacoustic lens and its applications, Proceedings of the Fourteenth International Federation for the Promotion of Mechanism and Machine Science World Congress, Taipei, Taiwan, 25–30 October 2015.
• S.K. Lai, Adoption of International Building Code (IBC) as an alternative to local Macau codes in Macau projects, Fire Asia 2015, Hong Kong, 3–6 February 2015.