Sequoia Scientific
Science in Johannesburg

For two decades, field, has been the world’s only manufacturer of portable, WA, Inc. in Bellevue, Sequoia Scientific, and submersible laser particle sizers.

Since 1995, Sequoia Scientific, Inc. has been the global leader in technologies for submersible and field measurements of particles and particle size distributions. This was the first instrument which incorporated laser diffraction technology for measuring particles in coasts, ports, harbors, rivers, streams, and reservoirs etc. It remains the only instrument worldwide with this capability. An iso-kinetic sensor system, LISST-SL was developed to measure sediments and other parameters for monitoring rivers. It is used, among others, by drillers in the oil and gas industry to size drilling muds. These various sensors are in use by US and 30-plus international government agencies, academics, consulting, and environmental monitoring companies. In 2011, the company introduced its first in-line holographic particle measuring instrument, LISST-HOLO. The meeting is organized by Sequoia and a local organizer somewhere in Europe. Later he developed LDV’s for combustion research, and then shifting to ocean science, he built autonomous systems for use on deep ocean bottom, in shallow seas, and lakes. This interest in sediment transport in coastal and ocean boundary layers introduced him to laser diffraction technology for particle size measurements. Yogi’s most recent interest is in high-frequency acoustic backscatter measurement of particles. Much of my early research at Sequoia sought to improve remote sensing of optically shallow water. That work involved the development and evaluation of spectrum-matching methods for retrieval of bathymetry, bottom classification, and water inherent optical properties from airborne hyperspectral imagery. One result of that work is the extremely fast EcoLight-S(ubroutine) radiative transfer code, which is designed for use as the optical component of coupled physical-biological-optical ocean ecosystem models. Our vacations now find us paddling in exotic locations around the world. Our kayaking expeditions have included Alaska, Greece, arctic Norway, eastern Greenland, Panama, and Fiji. Thoughts of Antarctica are now becoming more frequent. Most, if not all, included some kind of optics and electronics. All of which were in-situ instruments that required close coupling of electronics, optics and mechanical components. I’m happy to be part of a team that does that all the time. My research focuses on characterization of oceanic particles and their dynamics using optical methods, especially using multi-spectral, multi-angle, and polarized measurements of inherent optical properties. As a research scientist at Sequoia Scientific, one of my primary aims is the development of instrumentation and methods for measuring particle optical properties and the deployment of these technologies in observing systems, ship-based flowthrough systems, and on autonomous and other challenging platforms. Improving understanding of the links between optical properties and particle size.