9 October 2015
S2S Building, 18 Kent Ridge Road, Singapore 119227
1400 Welcome by Chair
1410 Technical Talk:
Prof. Pablo Valdivia y Alvarado Assistant Professor, SUTD
Title: Modeling and Control of Soft Body Underwater Fin Locomotion.
Abstract:The approaches to locomotion in liquid environments found in nature are very diverse. However, a common theme
is the use of soft and flexible fins or appendages for momentum transfer. Unlike locomotion on land, where discrete
point forces can reliably be used to model the reaction forces needed to transfer momentum, the fin generated
pressure fields that provide the reaction forces needed for underwater locomotion are more complex. In this talk I
will discuss the development of a simple model to estimate underwater locomotive forces and enable real-time
control of bio-inspired fin propelled vehicles.
Bio: Pablo Valdivia y Alvarado obtained his B.S., M.S., and Ph.D. degrees in Mechanical Engineering at the
Massachusetts Institute of Technology. Dr. Valdivia y Alvarado is an Assistant Professor in the Engineering
Product Development Pillar at the Singapore University of Technology and Design (SUTD) and a Research
Affiliate in the Mechanical Engineering Department at MIT and the Center of Environmental Sensing and Modeling
at the Singapore-MIT Alliance for Research and Technology. His research interests include Bio-inspired design,
Soft-under-actuated robots and sensors, and Modeling of locomotion in fluid environments. Dr. Valdivia y Alvarado
was recognized with a TR35 young innovator award for South East Asia, Australia and New Zealand in 2012 for his
work on soft robots for harsh environments. His doctoral work on the design of bio-inspired soft-robots received a
considerable amount of publicity worldwide with articles appearing in CNN, the Discovery Channel, National
Geographic, and Wired Magazine among others. His work is also featured in the permanent exhibition, “A Journey
Through Creativity”, at the ARTSCIENCE Museum in Singapore.
1450 Technical Talk:
Dr. Daniel Tan Bien Aik, DSO
Title: Estimating geoacoustic parameters using underwater acoustic remote sensing methods.
Abstract: Assuming the signal measured at the receiver is some distance away from a source, the general idea in
geoacoustic inversion is to optimize the forward model parameters by minimizing the difference between the
measured and replica acoustic signal. In doing this, we estimate sediment properties without resorting to costly
direct measurements such as sediment coring. Knowing the seafloor acoustic properties is important for various
applications such as sonar performance prediction, source localization and, detection and classification of
underwater man-made objects. However, matched field inversion typically uses large aperture arrays and powerful
transmissions to reduce parameter estimation uncertainty.
Bio: Bien Aik Tan received the B.Eng. degree in electrical engineering from the National University of Singapore,
Singapore in 2001. He received the M.Eng. Degree from the National University of Singapore in 2006. He also
graduated with a Ph.D. in electrical and computer engineering (Signal and Image Processing) from the University of
California, San Diego in 2014. His area of interests lies mainly in inverse problems, statistical signal processing,
signal analysis, array signal processing, ocean acoustics, underwater communications and geoacoustic inversion.
He is now with DSO National Laboratories, Singapore.
1530 Technical Talk:
Dr. Gonzalo Carrasco, Postdoctoral Associate, SMART
Title: Zinc Complexing Ligands In A Tropical Pristine River, An Anthropogenicaly Influenced River And In
Peatland In The West Pacific Region: Understanding The Connection To Regional And Global Distributions
Of Zinc Ligands And Bioavailable Zinc.
Abstract: Organic complexing ligands dominate the chemical speciation of Zn in seawater globally, affecting its
bioavailability and regulating its micronutrient role. We have shown that intermediate water masses in the West
Pacific indicate a connection between point sources related to marginal seas, riverine matter, benthic fluxes, and
continental shelves, with ligand concentrations and binding strengths evolving along water mass trajectories.Here
we will present preliminary results of studies in the West Pacific region that explore rivers in the region with and
without anthropogenic influence, and water taken from peatlands in Borneo, with the aim of elucidating the relative
importance of relatively fresh land-based plant material in this natural organic matter mix that the ligands are a part
of. We will compare it with the ligands observed in continental shelves, where the organic matter has suffered
biochemical processes, with ligands observed in the West Pacific, after decades of bacterial respiration while
travelling along water masses. We aim to compare these ligand in order to assess the relevance of these sources
of complexing ligands to regulate regional and global distribution of Zn ligands and its bioavailable concentratin.
Bio: Dr Carrasco obtained his BSc in Pharmacy and Biochemistry at the Universidad Catolica Santa Maria in Peru,
studying Chromium in the river-water-plant ecosystem of the Chili River in Arequipa, Peru. He continued
investigating trace metals, expanding into the bioavailable concentrations of Zinc and Cadmium in the South
Atlantic and the West North Pacific Oceans and in the Elizabeth River, Norfolk, Virginia, as part of his MsC and
PhD in Chemical Oceanography at Old Dominion University. He then moved to work on the isotopic ratios of trace
metals as a tool to investigate sources and processes these trace metals undergo, which he studied in several
projects he was involved with as a Postdoctoral Researcher at the Massachusetts Institute of Technology. These
projects included water and sediments off of the Guanabara Bay in Rio de Janeiro, Kuwait Bay in Kuwait, and the
North Atlantic and the North Central Pacific. He moved to Singapore in 2014 and has been establishing a trace
metal clean lab and developing local and regional collaborations in South East Asia, based at the Centre for
Environmental Sensing and Modeling at the Singapore-MIT Alliance for Research and Technology, where he is a
1610 Technical Talk:
David Velasco, Nortek AS
Title: Advances in Long Range Current Profiling with Composite Broadband Transducers.
Abstract:As with most current measurement projects in oceanographic applications, long range (> 300 m) current
measurement techniques have always been subject to tradeoffs between competing parameters, such as profiling
range, power consumption, desired spatial/temporal resolution, and transducer directivity. These tradeoffs are
largely controlled by the choice of signal processing technique and transducer type. In an attempt to improve
instrument flexibility for long range current profiling applications, Nortek AS has developed an instrument (called
Signature55) employing both Narrowband and Broadband processing techniques, powered by a low noise and low
power consumption electronics, that is capable of >1000 m current profiling measurements. At the core of this
instrument are wide bandwidth composite transducers designed by its subsidiary, Nortek Piezo. The composite
transducers are capable of operating both at 55 kHz with a 6% bandwidth, as well as at 75 kHz with 25% bandwidth.
The present work describes the development of the Signature55 system, with a focus on the composite broadband
transducers, and presents examples of its practical use in oceanographic applications.
Bio: David Velasco is responsible for Business Development for Nortek AS in Asia Pacific. He is based in Singapore and
has been working in the acoustic Doppler technology industry since 2002. He has extensive experience in the
development and use of analytical instrumentation for water quantity and quality monitoring (specific acoustic
Doppler instrumentation). He has worked throughout North and South America as well as in Asia Pacific.
1640 Group Photo Session & SAUVC update from committee chair.
1700 Industry Talk : SALT
1720 Industry Talk : Seatronics
1740 Annual General Meeting for all OES members.
1800 BBQ Dinner sponsored by Sea and Land Technologies.