https://hdl.handle.net/1721.1/96971 Mon, 06 Apr 2026 15:17:25 GMT 2026-04-06T15:17:25Z https://hdl.handle.net/1721.1/97033 Ballast Water Exchange in the North Atlantic Pederson, Judith; Fertig, Benjamin This white paper focuses on the regional component of ballast water management and specifically addresses concerns in the Gulf of St. Lawrence and Gulf of Maine. It summarizes vessel traffic and ballast water exchange in this region, and recommends cooperation between Canada and the U.S. to (a) examine the feasibility of alternate ballast exchange areas within the Exclusive Economic Zone for the Northwest Atlantic, (b) support continued data collection on ship traffic and ballast exchange, (c) continue support for research on risk assessment, and (d) support development of alternative ballast water treatments. Thu, 01 Jan 2004 00:00:00 GMT https://hdl.handle.net/1721.1/97033 2004-01-01T00:00:00Z https://hdl.handle.net/1721.1/97032 Marine Invaders in the Northeast: Rapid Assessment Survey of Non-native and Native Marine Species of Floating Dock Communities, August 2003 Pederson, Judith; Bullock, Robert; Carlton, James; Dijkstra, Jennifer; Dobroski, Nicole; Dyrynda, Peter; Fisher, Ryan; Harris, Larry; Hobbs, Niels; Lambert, Gretchen; Lazo-Wasem, Eric; Mathieson, Arthur; Miglietta, Maria-Pia; Smith, Jan; Smith III, Julian; Tyrrell, Megan In his seminal book on The Ecology of Invasions by Animals and Plants, Elton (1958) laid the foundation for the science of biological invasions. He identified the importance of human-mediated vectors as means of transporting organisms to new locations and discussed invasions in the context of ecological impacts and evolutionary consequences. Elton even identified what needed to be done to prevent practical and ecological damages from invaders--keep them out, eradicate them, and if all else fails, manage them at acceptable levels. We have not been vigilant in applying this knowledge to marine ecosystems, although this is changing. Our ability to detect changes in numbers and rate of marine introductions depends on well-documented lists of species in time and space, appropriate identification of non-native species, and careful records that follow changes in nomenclature, distribution, potential vectors, and ecosystem alterations caused by non-native species. Sat, 01 Jan 2005 00:00:00 GMT https://hdl.handle.net/1721.1/97032 2005-01-01T00:00:00Z https://hdl.handle.net/1721.1/97031 Reconfigurable Modem for Ocean Observatories Sozer, Ethem Mutlu Acoustic communications is an important part of underwater research. The mass amount of data collected by sub-sea devices can be made available to the scientific community in real-time with the utilization of acoustic modems. Sat, 01 Jan 2005 00:00:00 GMT https://hdl.handle.net/1721.1/97031 2005-01-01T00:00:00Z https://hdl.handle.net/1721.1/97030 Affordable Deep Ocean Exploration with a Hovering Autonomous Underwater Vehicle: Odyssey IV: a 6000 Meter Rated, Cruising and Hovering AUV Polidoro, V.; Desset, S.; Chryssostomidis, Chryssostomos; Hover, Franz S.; Morash, J.; Damus, R. The Autonomous Underwater Vehicle Laboratory (AUVLAB) at the Massachusetts Institute of Technology (MIT) is currently building and testing a new, general purpose and inexpensive 6000 meter capable Hovering Autonomous Underwater Vehicle (HAUV), the 'ODYSSEY IV class'. The vehicle is intended for rapid deployments, potentially with minimal navigation, thus supporting episodic dives for exploratory missions. For that, the vehicle is capable of fast dive times, short survey on bottom and simple navigation. This vehicle has both high speed cruising and zero speed hovering capabilities, enabling it to perform both broad area search missions and high resolution inspection missions with the same platform. Sat, 01 Jan 2005 00:00:00 GMT https://hdl.handle.net/1721.1/97030 2005-01-01T00:00:00Z https://hdl.handle.net/1721.1/97029 Adapting a Survey-Class AUV for High Resolution Seafloor Imaging Morash, James; Damus, Robert; Desset, Samuel; Polidoro, Victor; Chryssostomidis, Chryssostomos Over the past four years, development work at the MIT AUV Lab focused on a vehicle that is now almost a decade old. “Xanthos,” one of the last surviving examples of the venerable Odyssey II series of AUVs (developed at MIT in the early 1990s), is a small, deep-rated, low- drag vehicle originally intended for oceanographic survey work. In this project, the AUV Lab pushed the limits of the Odyssey II platform to bring this aging vehicle up to the state of the art in underwater imaging. Originally designed to carry a CTD and ADCP, Xanthos was refit with DVL and AHRS for navigation, and sidescan sonar, high-resolution digital still camera, and high-powered strobe for seafloor imaging. No part of the original vehicle was left untouched; several subsystems were redesigned and rebuilt from scratch to accommodate the new sensors. The ultimate goal: to turn a simple CTD profiler into a tool for deep-water marine archaeology. Xanthos’ rebirth culminated in a visit to Greece, aboard the Hellenic Center for Marine Research’s R/V “Aegaeo.” This attempt at AUV-based archaeology demonstrated the strengths and weaknesses of the re-design, as Xanthos contended with strong currents, navigation failures, sensor limitations, and mechanical damage. Lessons learned from the development of Xanthos as an imaging platform form the foundation of the MIT AUV Lab’s latest project. The “Odyssey IV,” capable of hovering and holonomic maneuvers at depths of up to 3000m, will carry a stereo camera and sonar as its primary sensor payloads. Sat, 01 Jan 2005 00:00:00 GMT https://hdl.handle.net/1721.1/97029 2005-01-01T00:00:00Z https://hdl.handle.net/1721.1/97028 Linearized Hovering Control With One or More Azimuthing Thrusters Hover, Franz S. We propose a simple method of control system design for marine vehicles with one or more azimuthing propulsors, and specifically for the case where the speed of the actuator is on the same time scale as the plant dynamic response, thus making the assumption of a separation of time scales invalid. By setting a fixed, regular azimuth trajectory, the control problem is simplified sufficiently to allow a fully linear design approach, for which bandwidth achieved, robustness, and disturbance and noise rejection, will be more tangible than in the nonlinear cases. Several simulation examples are presented for a new vehicle that is in development; the approach would apply directly to the cases of multiple propulsors and dynamic positioning as well. Mon, 01 Jan 2007 00:00:00 GMT https://hdl.handle.net/1721.1/97028 2007-01-01T00:00:00Z https://hdl.handle.net/1721.1/97027 Adaptive Management for Impacts to Eelgrass Habitat in Gloucester Harbor Wilbur, Anthony R.; Wilbur, Brandy M. M.; Colarusso, Phil The Massachusetts Office of Coastal Zone Management and the Massachusetts Institute of Technology Sea Grant College Program, along with partners, led an effort to create an eelgrass bank, raise awareness of the value of eelgrass habitat, and facilitate transplanting efforts to Boston Harbor in the summer and fall of 2006. A planned impact to eelgrass habitat in Gloucester Harbor warranted efforts to try to save this valuable and declining resource. This unfortunate circumstance was used to educate interested citizens, students and teachers from regional schools, and government employees. Methods to transplant and store eelgrass were researched and tested in attempt to facilitate restoration of the impact area. Two community events were organized at Pavilion Beach to harvest eelgrass from the impact area. These events were attended by a variety of government (city, state, and federal) and non-government employees, along with students and teachers, and attracted much attention of the citizens of Gloucester. Eelgrass was successfully transplanted to Boston Harbor by the Massachusetts Division of Marine Fisheries. Harvested eelgrass was also maintained in a hydroponic raft system for three months (October-December) and used to set-up an interpretative display in a flow-through tank at the Gloucester Maritime Heritage Center. While the harvested eelgrass was ultimately not transplanted back to the impact corridor, experience in storing eelgrass within hydroponic and tank systems could assist future restoration efforts. By teaming up to save the eelgrass at Pavilion Beach in Gloucester Harbor, project partners demonstrated the advantage of creative, adaptive, and cooperative efforts to manage coastal resources. The project was a learning experience in adaptive management for eelgrass habitat and a success in outreach. Mon, 01 Jan 2007 00:00:00 GMT https://hdl.handle.net/1721.1/97027 2007-01-01T00:00:00Z https://hdl.handle.net/1721.1/97026 Lateral-Line Inspired MEMS-Array Pressure Sensing for Passive Underwater Navigation Fernandez, Vicente Ignacio; Hou, Stephen M.; Hover, Franz S.; Lang, Jeffrey H.; Triantafyllou, Michael S. This paper presents work toward the development of a novel MEMS sensing technology for AUVs. The proposed lateral line-inspired sensor system is a high-density array of pressure sensors for measuring hydrodynamic disturbances. By measuring pressure variations on a vehicle surface, a dense pressure sensor array will allow the AUV to detect, classify, and locate nearby obstacles and optimize its motion in unsteady environments. This approach is very similar to the canal lateral line system found in all fish, which allow them to function in dark or clouded environments. In order to lay the groundwork for developing the MEMS sensor and interpreting the pressure distributions, the paper also presents experiments demonstrating the discrimination between cylindrical obstacles of round and square cross sections with an array of off-the-shelf pressure sensors. Test objects with 5.1 cm and 7.6 cm diameters passed stationary sensors at 0.5 m/s and 0.75 m/s and with 1.3 and 5.1 mm separation. Hand chosen features and features chosen through a Principal Component Analysis are used to discriminate between object shapes under a variety of conditions. A classification error rate of under 2% is achieved across all velocities, sizes, and separations. These results lead to requirements for the density, sensitivity, and frequency response of the MEMS sensors, which fall well in the MEMS domain. The pressure sensor array proposed here consists of hundreds of MEMS pressure sensors with diameters near 1 mm spaced a few millimeters apart fabricated on etched silicon and Pyrex wafers; a fabrication process for producing the array is described. A strain-gauge pressure sensor is analyzed and shown to satisfy specifications as required by the results from the afore-mentioned experiments. The sensing element is a strain gauge mounted on a flexible diaphragm, which is a thin (20 µm) layer of silicon attached at the edges to a square silicon cavity 2000 µm wide on a side. A source voltage of 10 V produces a sensor with a sensitivity on the order of 1µV/Pa. Since the thermal noise voltage is near 0.7 µV, the pressure resolution of the sensors is on the order of 1 Pa. Sun, 01 Jul 2007 00:00:00 GMT https://hdl.handle.net/1721.1/97026 2007-07-01T00:00:00Z https://hdl.handle.net/1721.1/97025 AUVNetSim: a Simulator for Underwater Acoustics Networks Montana, Josep Miquel Jornet AUVNetSim is a simulation library for testing acoustic networking algorithms. It is written in Python and makes extensive use of the SimPy discrete event simulation package. AUVNetSim is interesting for both end users and developers. A user willing to run several simulations using the resources that are already available, can easily modify several system parameters without having to explicitly deal with Python code. For example, a developer who wants to include a new MAC protocol can simply do so by taking the advantage of the existing structure. Thu, 01 May 2008 00:00:00 GMT https://hdl.handle.net/1721.1/97025 2008-05-01T00:00:00Z https://hdl.handle.net/1721.1/97024 Design of the All-Electric Ship: Focus on Integrated Power System Coupled to Hydrodynamics Prempraneerach, P.; Kirtley, James L., Jr.; Chryssostomidis, Chryssostomos; Triantafyllou, Michael S.; Karniadakis, George E. We present a detailed model of the integrated power system coupled to hydrodynamics that allows us to study global sensitivities in the All-Electric Ship. A novel element of our formulation is the stochastic modeling of the coupled system to account for uncertainty in the parameters or operating conditions. This new computational framework is applied to a model of the DDG- 51 destroyer that involves a 19 MW 15-phase induction machine and an indirect field oriented controller. In particular, we simulate extreme events corresponding to propeller emergence and firing of pulsed power weapons. Tue, 01 Jan 2008 00:00:00 GMT https://hdl.handle.net/1721.1/97024 2008-01-01T00:00:00Z https://hdl.handle.net/1721.1/97023 Gradient-Free Stochastic Sensitivity Analysis of the Shipboard Power System Prempraneerach, P.; Foo, J.; Triantafyllou, Michael S.; Chryssostomidis, Chryssostomos; Karniadakis, George E. Sensitivity analysis results are useful both for the early design stage – where the parametric space can be substantially reduced – but also in operating conditions, e.g. of the future electric ship, resulting in reduced operational costs and increased reliability. Here we discuss variance-based methods to analyze the sensitivity of stochastic electro-mechanical systems with multirate dynamics. We present results for an illustrative example and for a model of an integrated power system. Tue, 01 Jan 2008 00:00:00 GMT https://hdl.handle.net/1721.1/97023 2008-01-01T00:00:00Z https://hdl.handle.net/1721.1/97013 Geographical Analysis of Ballast Water Data and Potential Threats of Invasive Species for the North Eastern United States Dassuncao, Clifton The globalization of consumer goods and natural resources has led to an unintentional increase in exchanges of native biota (Bright 1999, Barbier and Shogren 2004, Perrings et al. 2005). Organisms that were once constrained to niche native environments are increasingly finding means of transporting themselves to new territories where lack of predation and ideal living conditions allow for geographic takeover. Ballast water discharge and hull fouling have been identified as the main vectors for these introductions (Ruiz et al. 1997, Molnar et al. 2008) which end up causing billions of dollars in economic damage (Pimentel et al. 2005) and invaluable ecological harm (Gurevitch and Padilla 2004). Mon, 01 Dec 2008 00:00:00 GMT https://hdl.handle.net/1721.1/97013 2008-12-01T00:00:00Z https://hdl.handle.net/1721.1/97009 Gulf of Maine Strategic Regional Ocean Science Plan Pederson, Judith The Gulf of Maine Regional Ocean Science Initiative evolved from an awareness of the importance of integrated approaches to addressing ecological, environmental, and social influences in coastal and marine ecosystems at the regional level. In response to a call for regional coordination of research by the U.S. Commission on Ocean Policy, the National Sea Grant College Program funded ten projects to develop regional ocean research plans, one of which was awarded to the Gulf of Maine region. A Gulf of Maine Regional Ocean Science Council (ROSC) was appointed to oversee the development of a Strategic Regional Ocean Science Plan. The members include the Northeast Sea Grant College Program Directors and eight appointed members. The members, representing diverse areas of expertise from government, academia, and industry, include two Canadian representatives. Recognizing the importance of integrated approaches, this Gulf of Maine Strategic Regional Ocean Science Plan responds to the call for identifying priority themes that enhance ecosystem-based management and support coordination and collaboration of ongoing efforts. Sun, 01 Feb 2009 00:00:00 GMT https://hdl.handle.net/1721.1/97009 2009-02-01T00:00:00Z https://hdl.handle.net/1721.1/97008 Seeking Didemnum on Georges Bank Pederson, Judith Preliminary report of the MITSG Autonomous Underwater Vehicle cruise to Georges Bank on July 8-21 of 2008. The purpose of this cruise was to test the efficacy of an acoustic sensor in identifying the distribution of an aggressive sea squirt on Georges Bank that is threatening scallop and groundfish fisheries. Thu, 01 Jan 2009 00:00:00 GMT https://hdl.handle.net/1721.1/97008 2009-01-01T00:00:00Z https://hdl.handle.net/1721.1/97007 Development and application of distributed MEMS pressure sensor array for AUV object avoidance Fernandez, Vicente Ignacio; Hou, Stephen M.; Hover, Franz S.; Lang, Jeffrey H.; Triantafyllou, Michael S. A novel sensory system is being developed for AUVs to augment current sensory systems for navigation and operation in difficult environments. These environments are frequently cluttered and murky with substantial flow from currents or waves, frustrating sonar and vision systems while posing an increased risk to AUVs. In order to manage such situations, a better ability to locate and identify physical objects is needed. This gap could be filled by small low frequency pressure sensors distributed over the surface of the AUV in dense arrays. Wed, 01 Jul 2009 00:00:00 GMT https://hdl.handle.net/1721.1/97007 2009-07-01T00:00:00Z https://hdl.handle.net/1721.1/97006 Design and Performance of Odyssey IV: A Deep Ocean Hover-Capable AUV Eskesen, Justin; Owens, Dylan; Soroka, Michael; Morash, Jim; Hover, Franz S.; Chryssostomidis, Chryssostomos The Odyssey IV class AUV was designed to fill the evolving needs of research and industry for a deep rated (6000 meter) vehicle, which is capable of both efficient cruising and precise hovering. This AUV is powerful enough to reject currents typical in the open ocean environment and yet small enough to be deployed from a small fishing boat. The thruster layout, two vectored side thrusters and two fixed cross-body thrusters, allow for 4-DOF control, which gives this vehicle precision and flexibility not possible in previous Odyssey class AUVs. An adaptable payload area allows the mounting of sensors, actuators, or other hardware suitable to a particular mission. The dynamic control layer of our behavior-based MOOS software was completely redesigned to take advantage of the capabilities of this vehicle. This is also the first platform to utilize new graphical controls and database-driven logging which increase operator efficiency and make the vehicle safer to operate. Odyssey IV's intended uses include survey and inspection of cold water corals, fisheries, archaeological sites, and subsea infrastructure. It will also serve as a research platform for computer vision-based servoing and acoustic supervisory control. This paper will document the design considerations and implementation of the Odyssey IV, as well as report on a series of field tests culminating in its first scientific deployment at Georges Bank, observing and mapping the invasive tunicate Didemnum. Thu, 01 Jan 2009 00:00:00 GMT https://hdl.handle.net/1721.1/97006 2009-01-01T00:00:00Z https://hdl.handle.net/1721.1/97005 Scalability of Non-intrusive Load Monitoring for Shipboard Applications Paris, James; Remscrim, Zachary N.; Douglas, Keith; Leeb, Steven B.; Cox, Robert W.; Galvin, Scott T.; Coe, Steven G.; Haag, Jennifer R.; Goshorn, J. Andrew The non-intrusive load monitor has been demonstrated as an effective tool for evaluating and monitoring shipboard electro-mechanical systems through analysis of electrical power data. A key advantage of the non-intrusive approach is the ability to reduce sensor count by monitoring collections of loads. This paper reviews trade-offs that affect the likely performance of the NILM in a real world environment. Thu, 01 Jan 2009 00:00:00 GMT https://hdl.handle.net/1721.1/97005 2009-01-01T00:00:00Z https://hdl.handle.net/1721.1/97003 Field Demonstration of a Real-time Non-intrusive Monitoring System for Condition-based Maintenance Proper, Ethan; Cox, Robert W.; Leeb, Steven B.; Douglas, Keith; Paris, Jim; Wichakool, Warit; Foulks, Edward L.; Jones, Richard; Branch, Perry; Fuller, Ashley; Leghorn, Jeremy; Elkins, Greg The performance of important electrical loads on mission critical systems like warships or off-shore platforms is often tracked by dedicated monitoring equipment. Individual monitoring of each load is expensive and risky. Expense occurs because of the need for individual sensors and sensor wiring for every load of interest. Reliability is compromised because detected failures or fault conditions might legitimately be due to load failure, but might also be due to errors or failure in the sensor network or recording instruments. The power distribution network on a warship could be pressed into “dual-use” service, providing not only power distribution but also a diagnostic monitoring capability based on observations of the way in which loads draw power from the distribution service. This paper describes field tests of a prototype system that monitors multiple loads using existing electrical wiring. Initial results are presented from a device that monitors a small collection of motors and two other devices that monitor an entire engine room. Thu, 01 Jan 2009 00:00:00 GMT https://hdl.handle.net/1721.1/97003 2009-01-01T00:00:00Z https://hdl.handle.net/1721.1/97000 AUV NILM Update Cox, Robert; Leeb, Steven B. Work on the AUV NILM project has proceeded along two main fronts: (1) NILM System Development; (2) Diagnostics for Li-Ion Batteries Thu, 01 Jan 2009 00:00:00 GMT https://hdl.handle.net/1721.1/97000 2009-01-01T00:00:00Z https://hdl.handle.net/1721.1/96999 Touch-at-a-Distance: Pressure Microsensor Arrays for AUV Navigation Lang, Jeffrey H.; Hover, Franz S.; Triantafyllou, Michael S. Inspired by the lateral-line organ in fish, the ultimate objective of this project continues to be the development of a passive system for AUVs that can detect, classify and locate underwater objects. The lateral line sensory organ in fish enables some species to form three-dimensional maps of their surroundings. The canal subsystem of that organ acts as an array of pressure sensors. Interpreting spatial pressure gradients allows fish to perform a variety of actions from schooling, to tracking prey, to recognizing nearby objects. Similarly, by measuring pressure variations on a vehicle surface, an engineered dense pressure-sensor array could enable the identification and location of obstacles during navigation. Our navigation system is based upon two key technologies: (1) large arrays of very small pressure sensors that can be mounted on the surface of an AUV, and (2) the pressure signal processing algorithms through which object detection, classification and location is implemented. Correspondingly, this project is organized during its early years around the development of these two key technologies. Thu, 01 Jan 2009 00:00:00 GMT https://hdl.handle.net/1721.1/96999 2009-01-01T00:00:00Z https://hdl.handle.net/1721.1/96998 Temperature and Salinity Tolerances Predict Range Expansion for Two Invasive Marine Invertebrates Dassuncao, Clifton Aquatic invasions of nonindigenous species have increased dramatically due to the globalization of consumer goods, which relies on shipping to connect once isolated marine environments (Bright 1999, Barbier and Shogren 2004, Perrings et al. 2005). European waters have been shown to pose a particularly high threat to the northeastern United States due to the disproportionately large amount of shipping arriving from the area (Dassuncao 2008 unpublished) and the presence of invasive species, from regions outside Europe, currently established in European countries (Molnar et al. 2008). One European invader thought to be especially likely to arrive in the near future is the Australasian barnacle, Austrominius (=Elminius) modestus, (J. Pederson, MITSG, 2008), which has a long history in European waters (Crisp 1958, Harms and Anger 1989). Because A. modestus has been present in Europe for over 60 years, the question is why has it not appeared in the U.S? As fouling organisms, barnacles are among those species that are spread readily as invaders. Fri, 01 May 2009 00:00:00 GMT https://hdl.handle.net/1721.1/96998 2009-05-01T00:00:00Z https://hdl.handle.net/1721.1/96997 Towards amphibious robots: Asymmetric flapping foil motion underwater produces large thrust efficiently Licht, Stephen Carl; Wibawa, Martin; Hover, Franz S.; Triantafyllou, Michael S. The development of amphibious robots requires actuation that enables them to crawl as well as swim; sea turtles are excellent examples of amphibious functionality, that can serve as the biomimetic model for the development of amphibious robots. In this paper we have implemented the observed swimming kinematics of Myrtle, a green sea turtle Chelonia Mydas residing in the Giant Ocean Tank of the New England Aquarium, on the 1.5-meter long biomimetic vehicle Finnegan the RoboTurtle. It is shown that these kinematics result in outstanding performance in (a) rapid pitching, and (b) rapid level turning. The turning radius for the rigid hull vehicle is 0.8 body lengths, a remarkable improvement in turning ability for a rigid hull vehicle. Still Finnegan’s performance lags the live turtle’s performance by about 20%. Careful observations have shown that turtles employ a fin motion in-line with the direction of locomotion; this degree of freedom was not available to the Finnegan fins, as presently designed. Experimental tests on a flapping fin equipped with this third degree of freedom have shown that the in-line motion enhances the fin’s performance. This hydrodynamic result is doubly beneficial to an amphibious robot, because it allows for further enhancements in the hydrodynamic function of fins, while the in-line motion allows the same fins to be used for crawling on land. Thu, 01 Jan 2009 00:00:00 GMT https://hdl.handle.net/1721.1/96997 2009-01-01T00:00:00Z https://hdl.handle.net/1721.1/96996 Acoustic Communication Networks for Distributed Autonomous Underwater Platforms: Progress Report Stojanovic, Milica The ultimate goal of this project is to design and develop an experimental platform for testing and evaluation of mobile underwater acoustic networking. This report represents a cumulative summary of research and engineering efforts pursued from the beginning of the project up to this date. The project has focused on three topics: 1. Design and performance analysis of communication protocols for mobile acoustic networks; 2. Development of the software-defined reconfigurable acoustic modem; and 3. Design and development of a small autonomous underwater vehicle (the micro AUV). Thu, 01 Jul 2010 00:00:00 GMT https://hdl.handle.net/1721.1/96996 2010-07-01T00:00:00Z https://hdl.handle.net/1721.1/96995 Marine Introduced Species Q13: Are threats from marine invasive species increasing in Massachusetts and Cape Cod Bays? Pappal, Adrienne; Smith, Jan; Pederson, Judith Non-native species have emerged as one of the leading environmental threats to our coastal habitats. These species have been recognized globally as a major threat to biological diversity as well as to agriculture and other human interests. Human activities such as shipping, aquaculture, and recreation, can result in the transfer of species from their native ranges to new areas. Non-native species, once introduced, have the potential to spread rapidly and become invasive, resulting in profound, adverse effects on marine systems and economies. Along the coast of Massachusetts and around the world, scientists have witnessed numerous invasions and subsequent impacts. While most foreign species are harmless, there are many examples of plants and animals that have caused ecological and/or economic problems when moved to new areas. As some introduced species become invasive, the physical conditions and habitats of native species ca be altered in a variety of ways that result in the exclusion of native species and favor those of the invader. Invasives can cause a decrease a decrease in native species populations, a decline in native species diversity, alteration of habitat, and changes in nutrient dynamics or productivity. Invasive species can also result in major economic impacts resulting from losses of important commercial resources and expenditures related to control and management (e.g. zebra mussels that clog intake pipes for water systems in the Great Lakes). Fri, 01 Jan 2010 00:00:00 GMT https://hdl.handle.net/1721.1/96995 2010-01-01T00:00:00Z https://hdl.handle.net/1721.1/96994 Architectural Model to Enable Power System Tradeoff Studies Chryssostomidis, Chryssostomos; Chalfant, Julie; Hanthorn, David; Kirtley, James L., Jr.; Angle, Matthew G. We continue the development of an overall architectural model for an all-electric ship using a physics-based simulation environment to perform fully-integrated simulation of electrical, hydrodynamic, thermal, and structural components of the ship operating in a seaway. The goal of this architectural model is to develop an early-stage design tool capable of performing tradeoff studies on concepts such as AC vs. DC distribution, frequency and voltage level, inclusion of reduction gears, energy and power management options, and effect of arrangements and topology. The results of the studies will be presented in standard metrics including cost, weight, volume, efficiency/fuel consumption, reliability and survivability. We will specifically look at the hull, mechanical and electrical (HM&E) systems that support the ship and its missions; specifically, the electrical generation and distribution system, propulsion equipment, fresh- and saltwater pumping and distribution, control systems, and structural components. Sat, 01 Jan 2011 00:00:00 GMT https://hdl.handle.net/1721.1/96994 2011-01-01T00:00:00Z https://hdl.handle.net/1721.1/96993 Architectural Model to Enable Power System Tradeoff Studies (PPT presentation) Chryssostomidis, Chryssostomos; Chalfant, Julie; Hanthorn, David Sat, 01 Jan 2011 00:00:00 GMT https://hdl.handle.net/1721.1/96993 2011-01-01T00:00:00Z https://hdl.handle.net/1721.1/96992 Science and Technology Challenges and Potential Game-changing Opportunities Triantafyllou, Michael S. The future of naval engineering in the 21st century will be shaped by novel and emerging technologies that will not only provide unprecedented capabilities but also require radical rethinking of naval ship and vehicle design. This change is already in the works as engineering schools in major universities are hiring young faculty trained in new fields and developing novel technologies. This investment is expected to bring radical changes to mature fields, such as naval architecture and marine engineering; hence, to fully reap the benefits the ground must be prepared now. Sat, 01 Jan 2011 00:00:00 GMT https://hdl.handle.net/1721.1/96992 2011-01-01T00:00:00Z https://hdl.handle.net/1721.1/96991 Conserving Energy with No Watt Left Behind Leeb, Steven B.; Kirtley, James L., Jr. Facilities managers for industrial and commercial sites want to develop detailed electrical consumption profiles of their electrical and electromechanical loads, including expensive physical plant for heating, ventilation, and air conditioning (HVAC) and equipment for manufacturing and production. This information is essential in order to understand and optimize energy consumption, to detect and solve equipment failures and problems, and to facilitate predictive maintenance of electromechanical loads. As energy costs rise, residential customers are also developing a growing interest in understanding the magnitude and impact of their electrical consumption quickly, easily, and informatively. Fri, 01 Apr 2011 00:00:00 GMT https://hdl.handle.net/1721.1/96991 2011-04-01T00:00:00Z https://hdl.handle.net/1721.1/96990 MOOS-IvP Autonomy Tools Users Manual - Release 4.2.1 Benjamin, Michael Richard This document describes 19 MOOS-IvP autonomy tools. uHelmScope provides a run-time scoping window into the state of an active IvP Helm executing its mission. pMarineViewer is a geo-based GUI tool for rendering marine vehicles and geometric data in their operational area. uXMS is a terminal based tool for scoping on a MOOSDB process. uTermCommand is a terminal based tool for poking a MOOSDB with a set of MOOS file pre-defined variable-value pairs selectable with aliases from the command-line. pEchoVar provides a way of echoing a post to one MOOS variable with a new post having the same value to a different variable. uProcessWatch monitors the presence or absence of a set of MOOS processes and summarizes the collective status in a single MOOS variable. uPokeDB provides a way of poking the MOOSDB from the command line with one or more variable-value pairs without any pre-existing configuration of a MOOS file. uTimerScript will execute a pre-defined timed pausable script of poking variable-value pairs to a MOOSDB. pNodeReporter summarizes a platforms critical information into a single node report string for sharing beyond the vehicle. BasicContactMgr provides a basic contact management service with the ability to generate range-dependent configurable alerts. uSimMarine provides a simple marine vehicle simulator. uSimBeaconRange and uSim- ContactRange provide further simulation for range-only sensors. The Alog Toolbox is a set of offline tools for analyzing and manipulating log files in the .alog format. Fri, 01 Jul 2011 00:00:00 GMT https://hdl.handle.net/1721.1/96990 2011-07-01T00:00:00Z https://hdl.handle.net/1721.1/96989 An Overview of MOOS-IvP and a Users Guide to the IvP Helm - Release 4.2.1 Benjamin, Michael Richard; Schmidt, Henrik; Newman, Paul; Leonard, John Joseph This document describes the IvP Helm - an Open Source behavior-based autonomy application for unmanned vehicles. IvP is short for interval programming - a technique for representing and solving multi-objective optimizations problems. Behaviors in the IvP Helm are reconciled using multi-objective optimization when in competition with each other for influence of the vehicle. The IvP Helm is written as a MOOS application where MOOS is a set of Open Source publish-subscribe autonomy middleware tools. This document describes the configuration and use of the IvP Helm, provides examples of simple missions and information on how to download and build the software from the MOOS-IvP server at www.moos-ivp.org. Mon, 01 Aug 2011 00:00:00 GMT https://hdl.handle.net/1721.1/96989 2011-08-01T00:00:00Z https://hdl.handle.net/1721.1/96983 Dual Ring Bus Electrical Distribution System for US Navy Destroyer- and Frigate-sized Vessels Cooke, Chathan M.; Chalfant, Julie; Chryssostomidis, Chryssostomos In response to a Request for Information from the Office of Naval Research regarding electrical architectures to be considered in an architecture evaluation study for two candidate hull forms including a 10,000 ton destroyer-sized vessel and a 5,000 ton frigate-sized vessel, the Design Laboratory of the MIT Sea Grant College Program proposes a dual ring bus topology as described in the following. Sat, 01 Dec 2012 00:00:00 GMT https://hdl.handle.net/1721.1/96983 2012-12-01T00:00:00Z https://hdl.handle.net/1721.1/96982 Planning for the Future: Climate Adaptation in Hazard Mitigation Plans and Comprehensive Water Resource Management Plans Bailey, Gregory; Baril, Jacob A.; Bellini, Jonas A. This project investigated whether hazard mitigation plans (HMPs) and comprehensive water resource management plans (CWRMPs) completed by cities and towns in Massachusetts account for the long term effects of climate change. A hazard mitigation plan is documentation created by state officials or planners that states how a specific community prepares for potential hazards. A CWRMP is an assessment of current water infrastructure as well as a plan for future water management. As our group investigated climate change in coastal Massachusetts, we examined if current HMPs included climate change information. We then looked into the opportunities and barriers for climate change information being included in coastal community’s CWRMPs and HMPs. Finally, we provided recommendations to improve these plans as a resource for urban and environmental planners interested in planning for future climate change impacts. Thu, 01 Mar 2012 00:00:00 GMT https://hdl.handle.net/1721.1/96982 2012-03-01T00:00:00Z https://hdl.handle.net/1721.1/96981 Optimization of Lithium Iron Phosphate Battery Charging and Performance Misic, Aleksandar The goal of this project is to efficiently and safely charge a 5kWh battery pack in 15 minutes. Since the project is still in progress, this report describes experiments on a 56Wh battery. Experiments were performed to investigate various charging algorithms (Section 5.2.3), temperature effects (Sections 5.1.1-5.1.3 and 5.2.2) and long term health of the battery pack (Section 5.2.4). An introduction describing the motivation for the project is given in Section 1. Section 2 gives a detailed description of the equipment used including: cells, data acquisition devices, software, sensors, power sources and temperature control. Calculations performed on the data using Matlab are explained in Section 3. The methods for running experiments are described in Section 4. Section 5.1 gives the results for single cell experiments while Section 5.2 gives results for the battery pack. Some conclusions are drawn in Section 6. The report is followed by a few appendices which contain extra graphs. Mon, 01 Sep 2014 00:00:00 GMT https://hdl.handle.net/1721.1/96981 2014-09-01T00:00:00Z https://hdl.handle.net/1721.1/96980 Interim Report on S3D/LEAPS Integration Chalfant, Julie; Ferrante, Matthew D.; Noble, James A. The Naval Surface Warfare Center Carderock Division has created the Leading Edge Architecture for Prototyping Systems, or LEAPS, as the data repository for ship design, and a significant number of the early-stage ship design tools interface directly or through a translator with LEAPS. Separately, the Office of Naval Research has funded Smart Ship Systems Design (S3D), a ship design tool effort that expands the Navy’s toolkit to include simulation and distributed system design among other capabilities. The current project will integrate S3D with LEAPS. This report provides an interim status report on progress for the integration project. The project plan and use case are described, underlying terms are defined and correlated between the two databases, and the initial version of the translator code is described. Mon, 01 Sep 2014 00:00:00 GMT https://hdl.handle.net/1721.1/96980 2014-09-01T00:00:00Z https://hdl.handle.net/1721.1/96979 Parametric Optimization of S-type Cables Babaee, Hessam We formulated an S-curve parameterization for re-routing a cable path for a given offset displacement. In our approach we assume the cable path to follow a tangent hyperbolic curve. In our formulation, after taking the geometric constraints into account, two free parameters exist. The objective of our design is to maximize the curvature radius. We performed a full search in the two-dimensional design space to find the curvature radius for all possible design configurations. The two-dimensional distribution of curvature radius versus the design parameters is shown in a contour plot that can be readily used for design purposes. Wed, 01 Jan 2014 00:00:00 GMT https://hdl.handle.net/1721.1/96979 2014-01-01T00:00:00Z https://hdl.handle.net/1721.1/96978 System-level Modeling of Cooling Networks in All Electric Ships Babaee, Hessam A Thermal management simulation tool is required to rapidly and accurately evaluates and mitigates the adverse effects of increased heat loads in the initial stages of design in all electric ships. By reducing the dimension of Navier-Stokes and energy equations, we have developed one-dimensional partial differential equations models that simulate time-dependent hydrodynamics and heat transport in a piping network system. Beside the steady-state response, the computational model enables us to predict the transient behavior of the cooling system, when the operating conditions are time-variant. To accurately predict the impact of cooling system on temperature distribution at different ship's locations/components and vice versa, we coupled our computational tool with vemESRDC developed at Florida State University. We verified our implementation with several benchmark problems. Wed, 01 Jan 2014 00:00:00 GMT https://hdl.handle.net/1721.1/96978 2014-01-01T00:00:00Z