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6. Mapping Energy in the Boston Public Schools Curriculum

Author

Chen, Robert F., Scheff, Allison, Fields, Erica, Pelletier, Pamela, Faux, Russell, Chen, Robert F., editor, Eisenkraft, Arthur, editor, Fortus, David, editor, Krajcik, Joseph, editor, Neumann, Knut, editor, Nordine, Jeffrey, editor, and Scheff, Allison, editor

Published
2014
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7. Introduction: Why Focus on Energy Instruction?

Author

Eisenkraft, Arthur, Nordine, Jeffrey, Chen, Robert F., Fortus, David, Krajcik, Joseph, Neumann, Knut, Scheff, Allison, Chen, Robert F., editor, Eisenkraft, Arthur, editor, Fortus, David, editor, Krajcik, Joseph, editor, Neumann, Knut, editor, Nordine, Jeffrey, editor, and Scheff, Allison, editor

Published
2014
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8. Modifications of the local environment by natural marine hydrocarbon seeps

Author

Leifer, Ira, Clark, Jordan F, and Chen, Robert F

Subjects
Life Below Water, Meteorology & Atmospheric Sciences
Abstract

The bubble gas partial pressures, dissolved gas and oil, and fluid motions within the rising bubble streams of three shallow (< 70 m) natural hydrocarbon seeps in the Santa Barbara Channel were measured. Aqueous methane concentrations near the surface in the bubble plumes were substantially greater (> 108 times) than atmospheric equilibrium values: at two of the seeps it was slightly supersaturated with respect to the bubble's partial pressure. This indicates that the rate limiting step for methane. CH4 transfer into the water column was not bubble gas transfer, but rather turbulence transfer of water out of the saturated bubble stream to the bulk ocean. Strong upwelling flows were observed, as well as elevated fluorescence indicative of dissolved oils. At the bottom, bubbles are circa 90% CH4, but at the surface they were circa 60% CH4, 30% air, and 10% higher hydrocarbons.

Published
2000

25. A major biopolymeric component to dissolved organic carbon in surface sea water

Author

Aluwihare, Lihini I., Repeta, Daniel J., and Chen, Robert F.

Subjects
Marine biology -- Research, Biosynthesis -- Research, Photosynthesis research -- Analysis, Macromolecules -- Research, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Marine research indicates that neutral sugars, acetate and lipid molecules bond to form a common macromolecule used in photosynthesis. As much as seven-tenths of ultrafiltered dissolved organic matter and one-fifth of total DOC in surface sea water contains acyl oligosaccarides which have been synthesized through photosynthesis. Roughly equal measurements of macromolecular dissolved organic carbon are contained within photosynthesis building block molecules at sites in the Atlantic and Pacific oceans.

Published
1997

34. Metabolism of naphthalene, fluorene, and phenanthrene: preliminary characterization of a cloned gene cluster from Pseudomonas putida NCIB 9816

Author

Yang, Yujing, Chen, Robert F., and Shiaris, Michael P.

Subjects
Pseudomonas putida -- Genetic aspects, Polycyclic aromatic hydrocarbons -- Analysis, Biodegradation -- Analysis, Biological sciences
Abstract

Polycyclic aromatic hydrocarbon (PAH) transformation and metabolism are studied by analyzing phenanthrene, naphthalene and fluorene transformations in gene clusters cloned from Pseudomonas putida's NCIB 9816 strain. Four ring fission products and catabolic genes are detected. NAH7 upper pathway and NCIB 9816 cloned genes have similar genetic compositions but function differently during multiple PAH transformations. NCIB 9816 clones produce metabolites from three PAH's and NAH7 clones from naphthalene transformation.

Published
1994

40. AVIRIS calibration and application in coastal oceanic environments

Author

Carder, Kendall L, Reinersman, Phillip, Chen, Robert F, Muller-Karger, Frank, Davis, Curtiss O, and Hamilton, Michael

Subjects
Instrumentation And Photography
Abstract

The Airborne Visible-Infrared Imaging Spectrometer (AVIRIS) is a test-bed for future spacecraft sensors such as the High-Resolution Imaging Spectrometer and the Moderate-Resolution Imaging Spectrometers planned for the Earth Observing System. To use this sensor for ocean applications, S/N was increased by spatial averaging of images. Post-flight recalibration was accomplished by measuring in situ the water-leaving radiance at flight time, modeling its transmission to the aircraft, and adding modeled atmospheric radiance to that value. The preflight calibration curve was then adjusted until aircraft and modeled total radiance values matched. Water-leaving radiance values from the recalibrated AVIRIS imagery were consistent with in situ data supporting the validity of the approach. Imagery of the absorption coefficient at 415 nm and backscattering coefficient at 671 nm were used to depict the dissolved and particulate constituents of the Tampa Bay plume during late, ebb-tidal conditions.

Published
1993
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41. Unmixing of Spectral Components Affecting AVIRIS Imagery of Tampa Bay

Author

Davis, Curtiss O, Chen, Robert F, Lee, Z.P, and Carder, Kendall L

Abstract

Models have been developed for use with hyperspectral remote-sensing reflectance data collected just above the air-sea interface for the West Florida Shelf 1,2,3,4,. They respond to variations in pigment, detrital, and gelbstoff absorption, chlorophyll a and gelbstoff flourescence, water Raman Scattering, Backscattering by water and particulate, and bottom depth and albedo.

Published
1993

43. Adaptive Decentralized Control of Mobile Underwater Sensor Networks and Robots for Modeling Underwater Phenomena

Author

Detweiler, Carrick, Banerjee, Sreeja, Jiang, Mingshun, Peri, Francesco, Chen, Robert F., Chen, Robert, Doniec, Marek Wojciech, Rus, Daniela L, Massachusetts Institute of Technology. Computer Science and Artificial Intelligence Laboratory, Doniec, Marek Wojciech, and Rus, Daniela L

Subjects
0106 biological sciences, 0209 industrial biotechnology, Control and Optimization, Adaptive sensing, Computer Networks and Communications, Computer science, Real-time computing, adaptive sensing, 02 engineering and technology, lcsh:Technology, 01 natural sciences, depth adjustment, ocean, sensing, sensor network, 020901 industrial engineering & automation, Control theory, Underwater, Instrumentation, Simulation, lcsh:T, 010604 marine biology & hydrobiology, Volume (computing), Decentralised system, Underwater sensor networks, Robot, Wireless sensor network
Abstract

Understanding the dynamics of bodies of water and their impact on the global environment requires sensing information over the full volume of water. In this article, we develop a gradient-based decentralized controller that dynamically adjusts the depth of a network of underwater sensors to optimize sensing for computing maximally detailed volumetric models. We prove that the controller converges to a local minimum and show how the controller can be extended to work with hybrid robot and sensor network systems. We implement the controller on an underwater sensor network with depth adjustment capabilities. Through simulations and in-situ experiments, we verify the functionality and performance of the system and algorithm. Keywords: depth adjustment; adaptive sensing; ocean; sensing; sensor network

Published
2014

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