School of Mechanical, Electrical and Manufacturing Engineering

Staff

Dr Paul Lepper PhD BSc DIS MIOA

Photo of Dr Paul Lepper

Reader in Underwater and Bio Acoustics

Paul Lepper is specialises in the general field of underwater acoustics, bioacoustics and underwater technologies, including acoustic and optical underwater systems, sound field measurement and modelling, marine species hearing and acoustic impact of noise on marine fauna.

Current research topics include measurement and characterization of underwater noise sources and the assessment of noise impact on marine fauna. These topics have included work to assess the construction noise from several offshore windfarm developments, various petroleum platforms, and projects looking at noise from small leisure craft. This research has included source characterization, sound field modelling and modelling marine species exposure. He is also involved in projects to assess hearing abilities of marine mammals and the use of acoustic deterrents. Dr Lepper is also involved in the development of various systems for long term noise field assessment and passive detection of marine species and the use of various propagation models for sound field assessment.

Before returning to the Department of Electronic and Electrical Engineering in 2004 as A Senior Research Fellow Dr Lepper was a Research Fellow with the Optical Engineering Group, Wolfson School of Mechanical and Manufacturing Engineering, Loughborough University, where was working on the development and use of a Laser Doppler Velocimeter for measuring acoustic fields in water. Prior to that he was a Research Associate in the Underwater Acoustics Group, Department of Electronic and Electrical Engineering, conducting research on the development and use of a parametric sonar system for the identification and classification of sub-seabed sediment layers and sub-seabed objects by acoustic means.

From 2000 to 2003 he was a post-doctoral researcher at the Marine Physical Laboratory, Scripps Institute of Oceanography, University of California - San Diego, where he returned in 2009 for a sabbatical period of three months to carrying out research of acoustic propagation around underwater vehicles as an enhancement to passive source localisation and more recently the development of three dimensional scattering models.

Dr Lepper is a Member of the Institute of Acoustics (UK) and the Acoustical Society of America and life member of the Acoustical Society of India and acts a member underwater acoustics committee and events committee for the Institute of Acoustics.

Dr Paul Lepper was educated at Loughborough University in the Electronic and Electronic Engineering and Physics Departments. He is a Lecturer specializing in underwater acoustics, bioacoustics and related technologies with the Advanced Signal Processing Group at Loughborough a group with over 35 years of experience in underwater acoustics, assessment and technologies. Dr Lepper is currently involved in various projects relating to underwater noise (assessment and modelling) including measurement of noise from marine piling and offshore industrial operations, many in collaboration with NPL, and in 2008 in collaboration with Kolmarden Djurpark in Sweden developing equipment and performing assessment of noise impact from small leisure craft. He has also been involved in numerous exercises to assess noise impacts on marine life, requiring the use of state-of-the-art acoustic modelling techniques and knowledge of best current data for biological impact. In addition he is worked with various researchers to understanding marine species hearing, including pinnipeds and cetaceans and other projects related to the use of acoustic deterrents on fish species to prevent accidental entrapment.

From 2003-2004 he was working on the development and use of a Laser based vibrometry system for measuring sound underwater. Previously (1992-1999) he worked as a Research Associate in the Underwater Acoustics Group, at Loughborough before completing his PhD in 1999. During this period he was involved in numerous projects relating to bioacoustics, marine mammal hearing and assessment of underwater noise sources, with partners from industry and across Europe, USA and Asia. From 2000-2002 he was a post-doctoral researcher at the Marine Physical Laboratory, Scripps Institute of Oceanography, University of California - San Diego, USA carrying out an investigation of acoustic propagation around underwater vehicles. This period was complemented by a return visit to Scripps in 2009 for a three month sabbatical, working in the area’s of modelling of underwater environments and marine mammal acoustics and underwater noise.

Dr Lepper has over 60 publications in the area of underwater acoustics and bioacoustics. He is a member of the Institute of Acoustics and a member of the Underwater Acoustics Committee. He has been involved in organizing several conferences in the area of bioacoustics and has acted as chairman of the Underwater Noise, Measurement, Impact and Mitigation conference held in Southampton in 2008

Some examples of some recent research topics and publications include:

Various projects investigating underwater noise field measurement and assessment of percussion piling operations in UK windfarm sites and offshore petroleum platforms.

Various projects have been conducted in collaboration with the National Physical Laboratory (NPL) to assess sound fields and noise impacts for various offshore installations including windfarms and petrolium platforms.

These projects have including design and implementation of new procedures and technologies for acoustic measurements and detailed underwater acoustic field assessment during for example marine piling operations. As well the measurement in-situ radiated noise, state-of-the-art modelling techniques have been employed to assess potential acoustic zones of impact for various marine species. This includes detailed assessment of the potential noise field for a specific site (taking into account, sediment type, seabed topography etc.) and current known physiological and behavioural responses of various marine species to acoustic sources. Models were also developed to estimate cumulative sound field exposure to stationary or transiting marine species.

Example publications:

“The measurement of the underwater radiated noise from marine piling including characterization of a soft start period”, S.P. Robinson, P.A. Lepper & J. Albitt, Proceedings of the IEEE Oceans 07 conference, Aberdeen, 2007].

Potential impact of offshore windmill related sound on the communication of harbour porpoises in the North SeaCo-investigator partner in the collaboration with FTZ Westkueste, Keil, Germany to access the hearing capabilities and potential effects of radiated noise from a operational offshore windfarm.

Example publications:

''Perception of Low-frequency Acoustic Signals by a Harbour Porpoise (Phocoena phocoena) in the Presence of Simulated Offshore Wind Turbine Noise'' Lucke, K., P.Lepper, Hoeve, B., Everaarts, E., van Elk, N. and Siebert, U.,, Aquatic Mammals, May 2007].

''Testing the acoustic tolerance of harbour porpoise hearing for impulsive sounds'', Lucke, K., Lepper, P.A., Blanchet, M. and Siebert, U., Bioacoustics: The International Journal of Sound & Recording, 17(1-3), 2008, 329-331, ISSN 0952-4622.

Underwater noise assessment system from small leisure boats (BLUES)

Development of systems for analysis of underwater radiated noise from small leisure and work boats in shallow water and its potential effects on marine fauna.Investigation of acoustic deterrents to minimise entrapment of juvenile twaite shad (Alosa fallax)

Investigation of the ultrasonic acoustic deterrents’ to minimise fish entrapment in fresh water outflows from UK rivers

Characterization of radiated noise from a drilling operation in the North Sea. ''Diel echolocation activity of harbour porpoises (Phocoena phocoena) around North Sea offshore gas installations'', Todd, V.L.G., Pearse, W.D., Tregenza, N.C., Lepper, P.A. and Todd, I.B., ICES Journal of Marine Science Installations, 66, March 2009, pp 1-12, ISSN 101093/ICESJMS.

Supervisor of undergraduate part C and D final year projects:

Current PhD students are:

Trevor Rawlings (co-supervisor Prof. R. Kalawsky)

Distributed Control Architectures

Mohamad Zulkefli Adam (co-supervisor Dr S. Datta)

Unfamiliar Facial Identity Registration and Recognition Performance Enhancement

Steven Beesley (co-supervisor Dr S. Datta)

Error Concealment Based Optimisations for H.264

Selected Publications

"Technique for the calibration of hydrophones in the frequency range 10 to 600 kHz using a heterodyne interferometer and an acoustically compliant membrane", Theobald, P.D., Robinson, S.P., Thompson, A.D., Preston, R.C., Lepper, P.A. and Yuebing, W., The Journal of the Acoustical Society of America, p1185, 1st November 2005

"The measurement of the underwater radiated noise from a marine piling operation", Lepper P.A., Robinson S.P., Ablitt J. and Leonard, G., Proceedings of Pacific Rim Underwater Acoustics Conference, J. Acoust. Soc. Am, October 2007.

"The measurement of the underwater radiated noise from marine piling including characterisation of a 'soft start' period", Stephen P. Robinson, Paul A. Lepper, and Justin Ablitt, Proceedings of IEEE Oceans 2007, IEEE cat. 07EX1527C, ISBN: 1-4244-0635-8, 061215-074, Aberdeen, June 2007

''Perception of Low-frequency Acoustic Signals by a Harbour Porpoise (Phocoena phocoena) in the Presence of Simulated Offshore Wind Turbine Noise'', Lucke, K., P.Lepper, Hoeve, B., Everaarts, E., van Elk, N. and Siebert, U.,, Aquatic Mammals, May 2007.

"Measurement and Modelling of the Acoustic Field Near an Underwater Vehicle and Implications for Acoustic Source Localisation",Lepper, P.A. and D'Spain, G.L., Journal of the Acoustic Society of America, August 2007, pp 892-905,

"Monitoring the temporal and spatial characteristics of the noise radiated from marine piling (A)", Lepper P A and Robinson S P, , J. Acoust. Soc. Am., 123, p2987, 2008.

"Prediction of the cumulative exposure to underwater impulsive noise using both static and fleeing animal models (A)", Lepper P.A., Robinson, S. & Dible, S., Proceedings of the Institute of Acoustics, Underwater Noise, Measurement, Impact and Mitigation 2008 conference, Southampton,14-15 October 2008.

"The feasibility of remotely sensing marine sediments using a parametric array", Journal Society of Underwater Technology, Lepper, P.A. and Woodward, B., 8(0), pp 21-29, 2008.

"A methodology for the measurement of radiated noise from marine piling". Proceedings of the 3rd International Conference on "Underwater Acoustic Measurements: Technologies and Results", Greece, June 2009.

"Cumulative Noise Exposure Assessment for a Marine Environment Using Sound Exposure Level as a Metric", Theobald, P., Lepper, P.A, Robinson, S. and Hazelwood, D. Proceedings of the 3rd International Conference on "Underwater Acoustic Measurements: Technologies and Results", Greece, June 2009.

''Diel echolocation activity of harbour porpoises (Phocoena phocoena) around North Sea offshore gas installations'', Todd, V.L.G., P.A. Lepper, Pearse, W.D., Tregenza, N.C.,and Todd, I.B, ICES Journal of Marine Science Installations, March 2009.

"Temporal and Spectral Characteristics of a Marine Piling Operation in Shallow Water", Lepper P.A., Robinson, S. Ablitt J. Dible S., Proceedings of the NAG/DAGA 2009 International conference on Acoustics, Rotterdam, 23-26 March 2009.

"Temporary shift in masked hearing thresholds in a harbour porpoise (Phocena phocoena) after exposure to a seismic airgun stimuli", Lucke, K., Seibert, U., Lepper, P.A. & Blanchet, M-A., J.Acoust.Soc.Am, 125 (6), pp 4060-4070, June 2009.