Sea Grant Research Articles

Fuzzy guidance controller for an autonomous boat

A fuzzy guidance controller is developed for waypoint following guidance on a small autonomous boat. The boat is a prototype vehicle developed at the MIT Sea Grant College Program and is designed to perform autonomous oceanographic research. The fuzzy controller is programmed in C and down-loaded to a small onboard computer for execution. Navigation data is found in real-time using a digital compass and a differentially corrected GPS receiver. The fuzzy controller was found to be relatively easy to develop, simple to tune, and robust to external disturbances. Field test results are presented and show that the guidance controller performed well on complex paths.

Automated Bathymetry Using an Autonomous Surface Craft

A prototype autonomous surface craft (ASC) has been developed at the MIT Sea Grant College Program's Autonomous Vehicles Laboratory to collect bathymetric data in littoral regions economically. Potential uses of this data include coastal surveys and monitoring, mine countermeasure operations, and physical and biological oceanography. This paper describes the ASC and presents field experiment results. For bathymetric data to be of value, the precise location of each data point must be known. To accomplish this, the ASC uses a differentially corrected GPS-based fuzzy guidance controller to track to and cross a series of transect-defining way-points. The fuzzy controller is programmed in C and downloaded to a small on-board computer for execution. The fuzzy controller was found to be relatively easy to develop (not requiring a complex mathematical model of the vehicle's dynamics), simple to tune, and robust to external disturbances. Field test results are presented and show that the guidance controller performed well on complex paths.

The course of U.S. responses to global change: Can't we do better?

There have been enough words written about global environmental change but they have not brought clarity to our public discourse. In fact, what was once a calm rivulet of slow-moving, somewhat cloistered study has become a turbid torrent, a frothing flood of claims and counterclaims, aired in the press and the halls of Congress, on which researchers tide as uptight as they are able, buffeted by waves and vortices and apprehensive that they may capsize at any moment. In what follows I'll examine how this dramatic transition has occurred and identify actions needed to make the ride downstream smoother and safer for the nation and the world generally. Upstream, in the smaller, calmer flow of 30 years ago, a notably clear and prescient study carried out by the President's Science Advisory Committee (PSAC), and stimulated especially by Roger Revelle, summarized what was then known about increasing CO2 in the atmosphere, identified possible effects on global climate, and anticipated the development of numerical models capable of predicting climate change. 1 In that same year of 1965 the Environmental Science Services Administration (ESSA) was created, signalling recognition of the increased importance of broad environmental objectives as part of the federal agenda. This action was especially notable because it was carried out by federal administrators (Robert M. White and J. Herbert Hollomon) without Congressional prodding or recommendation by an external committee or commission. These events mark a time when governmental institutions were able to respond nimbly and promptly to new scientific insights and to emerging interests in environmental changes of global scale. Downstream, as flow of the river grew, turbulence increased. The Marine Resources and Engineering Development Act and the National Sea Grant Act were passed in 1966, and the Commission on Marine Science, Engineering and Resources (Stratton Commission) was appointed in 1967. These were responses to the interests of the marine resources community and of influential members of Congress in building a stronger federal capability for development of marine resources (oil, gas, minerals, energy, fish). In 1970 ESSA evolved into the new National Oceanic and Atmospheric Administration (NOAA), signalling an abrupt turn away from broad environmental science objectives toward resource development. True, creation of NOAA didn't result in much difference in what the components of the new agency actually did; in fact, that has been a continuing complaint of the marine resource community. But creation of NOAA and a heavy

The use of passive sonar to detect sound production and calculate population densities of penaeid shrimp in the Gulf of Mexico.

Past research concluded that nonstridulating pink shrimp (Penaeus duorarum) found in the Gulf of Mexico did not make sound in the sonic range, but might produce ultrasonic sound via friction between parts of the exoskeleton [W. R. Gehring, Sea Grant Bulletin ♯5 (1971)]. Recordings of ‘‘frying’’ noises over known penaeid shrimp beds led to speculation that the shrimp were mechanically producing the ‘‘frying’’ portion of the ambient noise, and that passive sonar might be used as a tool for penaeid shrimp detection and estimation of population densities [W. E. Evans, Acoustics Signature Catalog, 82–141 (1982)]. Sound production by nonstridulating white shrimp (Penaeus setiferus) of the Gulf of Mexico was studied using passive sonar. Video and hydrophone recordings were made of captive shrimp populations with known densities. Hydrophone recordings of wild populations were made pre‐ and postshrimp trawls, and trawl catch data were noted. Results showed that the captive shrimp produced detectable mechanical sound primarily via escape movements and possibly mastication. Initial comparison suggests that wild shrimp and captive shrimp sounds are similar. It is hoped that the final results of analysis will confirm that wild penaeid shrimp population density calculations are feasible using passive sonar data.

Effects of sound and ultrasound on Zebra Mussels.

The freshwater bivalve mollusk, Dreissena polymorpha – better known as the Zebra Mussel, since its introduction into the Great Lakes in 1985 has been quickly spreading throughout the waterways of both the United States and Canada causing serious economic and environmental consequences. The present study has been directed toward developing acoustic techniques to control Zebra Mussel infestation in various water intake and storage facilities. The effects of ultrasonic and hydrodynamic cavitation, low‐frequency sound and vibration on various life stage mussels (from eggs and larvae to adults) have been studied. It was found that cavitation can be used as a control measure for Zebra Mussel veligers. The efficiency of the ultrasonic and hydrodynamic cavitation treatments were measured as an output energy rate to achieve 100% mortality. Laboratory experiments demonstrated the effective use of low‐frequency waterborne sound to prevent Zebra Mussels from settling and translocating and to reduce reproduction abilities of mussels. [This work has been supported by Grant No. NA26RG0403‐01 from the NOAA to the Stevens Institute of Technology, New Jersey Sea Grant College Program.]

Taxonomy of Economic Seaweeds, With Reference to Some Pacific Species. Volume V Edited by Isabella A. Abbott (University of Hawaii). California Sea Grant College System, La Jolla, CA. 1995. xx + 254 pp. 15 × 23 cm. $10.00. No ISBN.

Taxonomy of Economic Seaweeds, With Reference to Some Pacific Species. Volume V Edited by Isabella A. Abbott (University of Hawaii). California Sea Grant College System, La Jolla, CA. 1995. xx + 254 pp. 15 × 23 cm. $10.00. No ISBN.

Networked Computing–A New Collaborative Tool for Making Two Heads Better than One!

ABSTRACT The size of the United States' coastal population is expected to increase dramatically by the year 2010, with more than 151 million additional people moving into coastal counties. This will result in our nation's coastal population swelling by nearly 27% since 1980. Rising pressures on fragile coastal resources will accompany this population growth. While increased regulation can reduce some anticipated environmental damage, university based outreach is seen as critical to advancing appropriate behavior by residents and visitors. Sea Grant outreach staff conducting this educational programming are spread over 36 states and territories. To overcome the handicap of disparate locations, networked computing is being pilot tested to increase collaboration between these marine Extension staff. Successful experiences to date suggest that emerging information technology can assist a wide variety of outreach professions to integrate their efforts.

Lake Erie sport and boat show patrons rank Great Lakes ecosystem health issues in 1993 and 1994

In 1993 and 1994 patrons of the Mid-America Boat Show and the American-Canadian Sport, Travel and Outdoor Show, both held in Cleveland, Ohio were asked to respond to an Ohio Sea Grant survey on Great Lakes issues. In 1993 and 1994, a list of issues, identified from previous surveys and citizen advisory groups, were presented to show patrons at the Ohio Sea Grant exhibit. They were asked to rank the importance of each issue on a scale of 0 to 6. A total of 1,751 and 987 boat show and sport show patrons responded in 1993 and 1994 respectively. The four highest ranked issues and their arithmetic means and standard deviations in 1993 and 1994 respectively, were: Lake Erie water quality (5.60±0.79 and 5.53±0.81); Eliminating persistent toxic substances in the Great Lakes (5.54±0.88 and 5.49±0.89); Protecting the Great Lakes ecosystem (5.49±0.87 and 5.51±0.80); and Toxic contaminants in fish (5.49±0.97 and 5.36±1.00). A t-test was used to compare means of 1993 and 1994 responses. Significant differences (≤0.05) occurred in mean responses for 9 out of 14 issues common to both the surveys. Factor analysis of 1993 data suggested that patrons of the 1993 shows: (1) have a strong concern for the Great Lakes ecosystem; and (2) recognize that individual actions count. Factor analysis of the 1994 data indicated that show patrons continued to have a concern for the Great Lakes ecosystem. Boat and outdoor show patrons (recreational resource users) are a constituency that can, if politically active, validate and support efforts to protect and preserve the Great Lakes ecosystem.

Book review

J. W. Good and S. S. Ridlington, eds. Coastal Natural Hazards: Science, Engineering, and Public Policy. 1992. Oregon Sea Grant, Oregon State University. 162 pp.

Reporting on risk: A journalist's handbook on environmental risk assessment : By Michael A. Kamrin, Dolores J. Katz, and Martha L. Walter The Foundation for American Communications (3800 Barham Boulevard, Suite 409, Los Angeles, California 90068) and Michigan Sea Grant (2200 Bonisteel Boulevard, Ann Arbor, Michigan 48109), 1995, 123 pp., softcover — $8.00

Reporting on risk: A journalist's handbook on environmental risk assessment : By Michael A. Kamrin, Dolores J. Katz, and Martha L. Walter The Foundation for American Communications (3800 Barham Boulevard, Suite 409, Los Angeles, California 90068) and Michigan Sea Grant (2200 Bonisteel Boulevard, Ann Arbor, Michigan 48109), 1995, 123 pp., softcover — $8.00

Aquatic Introductions Dispersal of Living Organisms into Aquatic Ecosystems Aaron Rosenfield Roger Mann

Aquatic Introductions Dispersal of Living Organisms into Aquatic Ecosystems. Rosenfield Aaron Mann Roger, eds. Maryland Sea Grant College, College Park, MD, 1992. 471 pp., illus. $35.00 (ISBN 0-943676-56-8 cloth). Paul Ringold Paul Ringold Office of Research and Development, US Environmental Protection Agency, Washington, DC 20460 Search for other works by this author on: Oxford Academic Google Scholar BioScience, Volume 44, Issue 9, October 1994, Pages 629–630, https://doi.org/10.2307/1312468 Published: 01 October 1994

M.M. Mullin Webs and scales. Physical and ecological processes in marine fish recruitment, xi, 135p. Washington Sea Grant Program, 1993. Price $25·00.

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Hemolymph lectins of the blue crab, Callinectes sapidus, recognize selected serotypes of its pathogen Vibrio parahaemolyticus.

Annals of the New York Academy of SciencesVolume 712, Issue 1 p. 324-326 Hemolymph Lectins of the Blue Crab, Callinectes sapidus, Recognize Selected Serotypes of Its Pathogen Vibrio parahaemolyticusa F. J. CASSELS, F. J. CASSELS Department of Gastroenterology Walter Reed A.I.R. Washington, D.C.Search for more papers by this authorE. W. ODOM, E. W. ODOM Center of Marine Biotechnology Maryland Biotechnology Institute University of Maryland System Baltimore, Maryland 21202Search for more papers by this authorG. R. VASTA, Corresponding Author G. R. VASTA Center of Marine Biotechnology Maryland Biotechnology Institute University of Maryland System Baltimore, Maryland 21202dAddress for correspondence: G. R. Vasta, Center of Marine Biotechnology, Maryland Biotechnology Institute, University of Maryland System, 600 E. Lombard St., Baltimore, MD 21202.Search for more papers by this author F. J. CASSELS, F. J. CASSELS Department of Gastroenterology Walter Reed A.I.R. Washington, D.C.Search for more papers by this authorE. W. ODOM, E. W. ODOM Center of Marine Biotechnology Maryland Biotechnology Institute University of Maryland System Baltimore, Maryland 21202Search for more papers by this authorG. R. VASTA, Corresponding Author G. R. VASTA Center of Marine Biotechnology Maryland Biotechnology Institute University of Maryland System Baltimore, Maryland 21202dAddress for correspondence: G. R. Vasta, Center of Marine Biotechnology, Maryland Biotechnology Institute, University of Maryland System, 600 E. Lombard St., Baltimore, MD 21202.Search for more papers by this author First published: April 1994 https://doi.org/10.1111/j.1749-6632.1994.tb33584.xCitations: 5 a Supported by NOAA Grant NA90AA-D-SG063 through the University of Maryland Sea Grant College to GRV and National Institutes of Health MARC Award 5 F31 GM14903–02 to EWO/GRV. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article.Citing Literature Volume712, Issue1Primordial Immunity: Foundations for the Vertebrate Immune SystemApril 1994Pages 324-326 RelatedInformation

Joining Hands for Quality Tourism: Interpretation, Preservation and the Travel Industry. Raymond S. Tabata, Jane Tamashiro, and Gabriel Cherem, eds. HII Congress, c/o UH Sea Grant, 1000 Pope Road, MSB 226, Honolulu, HI 96822. June 1992. 468p. $50 plus $5 postage and handling

Joining Hands for Quality Tourism: Interpretation, Preservation and the Travel Industry. Raymond S. Tabata, Jane Tamashiro, and Gabriel Cherem, eds. HII Congress, c/o UH Sea Grant, 1000 Pope Road, MSB 226, Honolulu, HI 96822. June 1992. 468p. $50 plus $5 postage and handling

W.G. Pearcy Ocean ecology of North Pacific salmonids. ix, 179p. Washington Sea Grant Program, University of Washington Press, 1992. Price $25.00 (cloth), $15.00 (paperback).

W.G. Pearcy Ocean ecology of North Pacific salmonids. ix, 179p. Washington Sea Grant Program, University of Washington Press, 1992. Price $25.00 (cloth), $15.00 (paperback).

Fine-scale biological and physical structure in stratified waters.

A new sampling technique is described that simultaneously allows collection of centimeter scale vertical profiles of plankton and the physical, chemical, and biological factors that can influence those distributions. A high-resolution electronic profiler is first used to define the vertical structure on centimeter scales of a series of electronically sensed parameters, then real-time analysis of data from the profiler is used in a second cast to collect pumped and siphoned samples from discrete layers for chemical and biological analysis. Application of these techniques in a permanently stratified estuary indicates that vertical distributions of zooplankton, their food resources, and potentially controlling biological, chemical, and physical factors can vary by up to an order of magnitude per 10 cm. A numerical analysis of these measured fine-scale structures indicates that conventional coarse scale sampling techniques can miss entire communities, grossly underestimate food resource availability, underestimate the sharpness in chemical and biological gradients that limit the vertical distributions of zooplankton, and confound efforts to evaluate acoustic sensor performance in the ocean. [Work supported by ONR and Sea Grant.]

Angler Associations as Partners in Walleye Management

Abstract Since 1986, over 310,000 walleye fingerlings, Stizostedion vitreum, (35–125 mm TL) have been cultured in earthen ponds and stocked into New York bays and tributaries of Lake Ontario. These introductions are unusual because the walleye fingerlings were produced and stocked through a cooperative effort involving seven angler associations, the New York Sea Grant Extension Program, the New York State Department of Environmental Conservation, and academia (particularly the State University of New York, College at Brockport and Cornell University). Based on several measures, the cooperative management program is a success. Cage studies indicate that 7–13-d survival of introduced fingerlings is high (>97%) and post-stocking samplings suggest that stocked fish contribute to the fisheries.

4-Hexylresorcinol and prevention of shrimp blackspot: Residual analyses

4-Hexylresorcinol is a potent inhibitor of shrimp melanosis or “blackspot” [ A. J. McEvily, R. Iyengar, and W. S. Otwell, 1991. Proceedings of the Fifteenth Tropical and Subtropical Fisheries Technological Conference, Florida Sea Grant Report No. 105, in press]. In order to estimate consumption of 4-hexylresorcinol as a consequence of its use in shrimp blackspot inhibition, residual levels of 4-hexylresorcinol on shrimp were quantified under several processing conditions. Shrimp treated using the recommended dip protocol of a 1-min dip into a 50-ppm 4-hexylresorcinol solution had mean residues s 1 ppm. Exposure to excessive concentrations of 4-hexylresorcinol (100 ppm) or extended dip times (15 min) resulted in increased residual values with a maximum value of 2 ± 0.8 ppm. The safety and functional advantages of 4-hexylresorcinol versus sulfite which is used currently for blackspot inhibition are discussed.

Spermatophore Structure and Anatomy of the Ejaculatory Duct in Penaeus setiferus, P. duorarum, and P. aztecus (Crustacea: Decapoda): Homologies and Functional Significance

Spermatophore Structure and Anatomy of the Ejaculatory Duct in Penaeus setiferus, P. duorarum, and P. aztecus (Crustacea: Decapoda): Homologies and Functional Significance

Next generation of seafloor samplers

The University of Washington, Seattle, has successfully completed the first stage of a proposed multiphase program to develop small rock drills as a new generation of seafloor sampling tools. Phase I of this program, a basic 3‐m drill, was funded by the National Science Foundation, the Office of Naval Research, and Washington Sea Grant. The drill was designed and built for the university by Williamson and Associates of Seattle and was successfully deployed, in 2400m of water on the Juan de Fuca Ridge, during August 1990. The present drill can penetrate and sample 3 m of vertically oriented core from crystalline igneous rocks, lithified sediments, and sulfide and carbonate deposits. It is deployable to a depth of 5000 m (limited by the cable and drill weight) by conventional research vessels using the NSF‐standard armored conducting cable. The drill is presently undergoing post‐test modifications at the University of Washington and will be available to the scientific community through a Regional Facility by summer 1991.