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The WHOI Micro-Modem is a compact low-power acoustic transceiver that can provide both acoustic telemetry and navigation. Its size and versatility make it ideal for integration in autonomous underwater vehicles (AUVs). The modem supports the use of both broadband and narrowband transponders for long baseline navigation systems has a modem-to-modem ranging capability and can be configured to provide synchronous one-way ranging when integrated with a precision clock. This paper gives an overview of the different navigation systems supported by the Micro-modem and presents the results from field tests conducted on the SeaBED AUV in deployments in Greece the Bluefin AUV and whale localizations in the Stellwagen Bank Marine Sanctuary.

Teleoperating ROV (remotely operated vehicles) underwater is a challenging and tedious task as the operators are physically removed from the sites and their situational awareness is low due to restricted camera views poor visibility underwater and limited 3D perception. Three vision system technologies are described that were originally developed for space applications. These will enable more efficient ROV operations. Automatic detection and tracking of artificial and natural targets will enable autonomous ROV station keeping (mooring) allowing the operators to focus on their main tasks. The 3D modelling system will create instantly models of underwater worksites and seafloor increasing thus operators' spatial perception and allowing measurements and precise manipulation tasks. Initial results of underwater experiments are presented and conclusions drawn.

The problem of constructing high quality mosaics of the sea bed is considered. The focus is on the use of long image sequences with time-distance superpositions such as the ones arising from loop trajectories or zig-zag scanning patterns. An algorithm is presented for the simultaneous creation of mosaics and the estimation of the camera trajectory. Some of the geometric concepts used throughout the text are briefly presented (section 2). The initial estimation of the homographies is described (section 3). The iterative scheme of matching-optimisation is presented where point correspondences between new pairs of images are searched for along with optimisation to refine the overall topology (section 4). The final trajectory estimation is described using the most general motion model which allows for the precise registration of images over a common world plane (section 5). Some selected results are presented in the form of final mosaics and VRML renderings of the camera path which testify to the good performance of the overall algorithm (section 6). Some discussion and conclusions are presented (section 7).

The first modern work to give a comprehensive picture of the RMS Titanic and the people intertwined with her fate, from disaster to recovery. Drawn from primary sources and contemporary accounts and updated to coincide with the April 2012 anniversary, this new heart-rending narrative allows readers to come to their own conclusions about this legendary vessel.Daniel Allen Butler spend more than 30 years researching the work, delving into the lives of every principal participant. In addition to examining the roles played by individual, he also looks into the problems of equipment and errors in technical data that resulted in the deaths of 1502 people. Rather than focussing on the night of the tragedy alone, he also investigates the events leading up to and following the fateful night.

Regional Coast Guard policy is introduced which provides guidance to marine safety personnel on the inspection of commercial diving operations during marine response operations. The goal of this policy is to protect the health and safety of commercial diving personnel. The background to this policy is presented and discussed. The policy itself is considered. This is followed by a commercial diving operation checklist. Finally tables are given detailing the requirement the OHSA regulation the USCG regulation and some commentary for each of commercial diving personnel commercial diving operations scuba diving operations surface supplied air diving and commercial diving equipment.

The mechanics of fatigue crack growth in metals and the resulting sources of stress-wave emission (acoustic emission) are described. Experience of monitoring fatigue crack growth in offshore steel jacket platforms drilling rigs and floating installations are described and the origin and magnitude of acoustic emission events their detection in high background noise and the determination of source significance discussed. It is shown that the energy released from different magnitude cleavage fracture events can be explained using the Griffith theory of fracture. The microfracture events contributing to stable fatigue crack growth in structural steels range in dimension from 25 to 500 microns. The resulting stress waves can be detected at distances up to several metres using an array of piezoelectric sensors attached to the structure. Applications experience monitoring crack growth in offshore structures during severe weather conditions is reviewed together with the requirement for a fatigue test database on the particular material and failure mechanism for the correct interpretation of results. Acoustic emission monitoring offers a practical solution to determining the integrity of a fatigue sensitive structure.

Since 1992 a series of experiments using recycled shredded exotic plant and garden waste have shown promising results as a tool for coastal upland restoration. Coastal ecosystem restoration of Tampa Bay (Florida) is a critical component of bay management plans drafted by the SWIM (Surface Water Improvement and Management) Programme of the Southwest Florida Water Management District and of the Tampa Bay National Estuary Program. Increasing emphasis is being placed on restoration of coastal upland systems. Efficient cost effective restoration and management tools are needed to meet habitat goals for Tampa bay. Mulching experiments are presented and results are presented and discussed and conclusions drawn. Lessons learned are then presented and recommendations proposed.

The prediction of overtopping discharge for seawalls and coastal structures is carried out using empirical formulas. They describe mean overtopping discharge or peak volumes using results gained from physical models for defined wave and structure parameters. For structure configurations or wave conditions not tested these methods may need extrapolating or may not even be valid at all. The studies to test the use of these models and to describe best practice are described. The efficient numerical models based on the non-linear shallow waters equation NLSW can reproduce wave trains of 1000 random waves extremely rapidly and have become very attractive for scheme design and flood forecasting. Generally NLSW models are an appropriate engineering tool for the calculation of wave runup and overtopping.

The Great Bay Estuary is a complex embayment on the New Hampshire and Maine border. The Estuary is a tidally dominated system and derives its freshwater inputs from seven major rivers. Located within the Boston corridor seacoast New Hampshire has experienced rapid population growth over the past ten years. As a result land protection has become a major priority of the Great Bay NERR (National Estuarine Research Reserve). The use of joint partnerships for protecting such coastal lands is addressed. Various joint initiatives are presented. These include: the North American Waterfowl Management Plan; the North American Wetlands Conservation Act; and the Great Bay Resource Protection Partnership; Habitat Protection Plan; the identification of some 25 areas of significant habitats and associated lands for acquisition and protection educational and outreach activities. Finally future goals are considered.

In this paper an attempt is made to bring a tentative solution to cover existing gaps in maintenance performance diagnostic systems in offshore engineering constructions. The new concept termed 'value based maintenance performance diagnostics' introduced in this paper illustrates the need for tangible-intangible synergies for a balanced performance assessment. In this effort value preferences for the petroleum industry are highlighted as the front-end governing areas of both macro and micro performance. Added-value and risk which presumably drive major performance based decisions are discussed in terms of the 'capital values'. Accordingly dimensions of maintenance performance that influence added-value and risk are identified. Based on the above a maintenance performance measurement architecture is proposed.

The heat left over from the formation of the planet combined with that generated by radioactive decay drives the internal engine of the Earth. This heat is the cause of elevated temperatures in mines and is the ultimate source of energy for volcanoes hot springs mountain building and earthquakes. The heat flux is the product of the temperature gradient and the thermal conductivity. Scientists use temperatures measured in boreholes coupled with conductivity measurements on the rocks penetrated to derive the heat flux through the continents. At sea they use the temperature gradient measured by thin probes driven into the soft sediments of the ocean floor multiplied by the thermal conductivity of these sediments. A personal retrospective of the attempt to explain Bullard's Law covering early heat flow surveys the sedimentary observations magnetic measurements and physical interference's that led to the realisation that fluid flowing through the oceanic crust must be responsible for the variability.

Environmental studies of disposal sites are directed by regulations that require extensive sampling of all biological chemical and physical characteristics of the sites with little regard for the application of this data to predicting real impacts on the environment. These studies are poorly focused provide little guidance for measuring actual impacts and are extremely costly. To address these problems a new method of carrying out environmental assessments of deep water dredged material disposal sites is presented that incorporates the latest developments in both video imaging and computer analysis as well as selective habitat based sampling. The method uses FOCUS ( a fiber optic camera under-sea system) which is relatively inexpensive and which permits real-time surveys of the sea floor. These surveys are taped and their locations recorded using GPS (Global Positioning System) to produce a permanent record of the sea floor at any given site. To test the feasibility and efficacy of the FOCUS system a series of transects are taken just seaward of the South O'ahu dredged material disposal site off Honolulu Hawaii. The results of these stuX46366

The research described in this paper concentrates on providing a flexible and integrated framework for management and decision support required by the different groups of users involved in fishery activities. Visualization is a very potent tool in the provision of decision support in fisheries information systems. This paper discusses the visualization capabilities of FishCAM2000 (FC) which is a computer-based integrated information system for fisheries management and marine environmental monitoring. Attention is given to the rationale for an integrated system followed by salient characteristics of the system. Next a look is taken at the methods covering system overview user interface primary data input and examples of user interface windows. This is followed by consideration of the results incorporating cartographic and graphical visualization of fishing activity and marine environmental modeling. Lastly there is discussion concerning visualization issues and implementation.

At present different methods for motion estimation and localisation of underwater vehicles exist mainly based on acoustic sensor networks. This strategy is relatively expensive. One cost-effective alternative can be to equip the vehicle with a downward-looking camera which acquires seafloor images while the robot is performing its mission. This downward-looking camera provides rich visual information that can be used for vehicle motion estimation. In most cases the process involves recovering the motion of the vehicle by means of gray level correlation or using optical flow. Unfortunately underwater images are difficult to process due to the medium of transmission characteristics. Blurriness of elements of the image cluttering and non-uniform illumination are some of the problems present in underwater imaging.

Papers volume for two-day international symposium 'Warship 2000 - Warships for Amphibious Operations & Minewarfare', held 6th - 7th June 2000, London. Contains 18 papers on the following: Warships for amphibious operations and Minewarfare, Alternative landing ship logistic, Combining LPD and aircraft carrier capabilities: A new Italian ship concept, San-Antonio-class LPD17, the HNLMS Rotterdam: the first RNLN LPD, Flight deck landing load diagrams, Mine warfare, Remote mine countermeasures, Joint modular lighter system, Ro-ro access equipment for amphibious operations, Air-assisted catamaran concepts for amphibious operations, High-speed military sea lift, Trimaran based concept for fast sea lift logistics ship and Precision Minewarfare autopilot.

Proceedings from two-day international symposium 'Warship '99: Naval Submarines 6', held 14-16 June 1999, in London. Papers within nine sessions: 1. Design (Soviet and Russian attack submarines), 2. Signatures (submarine acoustic target strength modelling, self noise monitoring system, 240 kW thermoelectric water chiller), 3. Senors and Data Management (non-hull penetrating masts and periscopes, Magnum: a new concept for submarine weapon handling and discharge, Data fusion and operability, 4. Design and Procurement (Royal Navy Astute class SSN, DCN Kockums, 5. Control and Manoeuvring (submarines, tab-assisted control surface), 6. Propulsion and AIP (submarine propulsion, fuel cell systems, AIP system tests, AIP selection), 7. Life Support (risk assessment of leakage from submarine chilled water plant, medical consequences in prolonged submerged patrol, 8. Emergency and Rescue (Submarine salvage systems, Recovery procedure in case of flooding, 9. Future Design (Asymmetric impacts of evolving SSK technologies on future naval deployments, The KAPPA project, BLC techniques usage in underwater shipbuilding, A foam sandwich submarine hull - Dera 'Novel Hull Model No. 1')

No warship name in British naval history has more battle honors than Warspite. This book examines the careers of all eight vessels to bear the name since 1596, but concentrates on the seventh vessel--the dreadnought battleship conceived as the ultimate answer to German naval power during the pre-World War I arms race. HMS Warspite fought off the entire German fleet at Jutland, survived a mutiny between the wars, and covered herself in glory during World War II. Flagship of Sir John Cunningham when he mastered the Italian Navy in the Mediterranean, Warspite's many wartime adventures included narrowly avoiding destruction by the Japanese carrier force that devastated Pearl Harbor and providing crucial fire support for Allied landings in Sicily, Italy, and Normandy. The voices of the men who fought aboard Warspite bring to life this stirring tale that will appeal to everyone with an interest in naval history and the ships that symbolized the great seafaring nation.

This paper presents numerical simulations of water-entry and water-exit of a circular cylinder with both forced and free vertical motions by using a Constrained Interpolation Profile-based (CIP-based) finite difference method. The circular cylinder and free surface interaction is treated as a multiphase problem while the free surface as well as the body boundary is immersed in the computational domain. One set of governing equations is used to represent the motion of different phases and these equations are solved numerically on a nonuniform staggered Cartesian grid by a finite difference method. The numerical results of the water entry and exit force the free surface deformation and the vertical motion of the cylinder are compared with experimental results and favourable agreement is obtained.

Hydrographic oxygen and nutrient data collected in the Nordic Seas during the 1990s is presented. This paper focuses on temporal variations in the conditions in the Greenland Sea mainly during the 1990s and relates such variations to fluctuating atmospheric conditions. The data suggests that almost no deep water has been formed since about 1970. Also it is shown that the deeper layers of the Greenland Basin were gradually filled with deep waters originating from the Arctic Ocean. Along the Greenland slope it is possible to distinguish water masses originating from the Canadian Basin from those originating from the Eurasian Basin. A description is given of the different pathways of these water masses in the Nordic Seas.

The water resources management in the marsh land has been analyzed and simulated by hydrological and hydraulic models to study the climatic change in the region of the Weser estuary. Attention is given to the water budget of the catchments in the estuary considering the inflow from upstream under climatic impact. The water balance was simulated for two characteristic years: the dry year 1991 and the wet year 1994. The impact on the water resources management due to climatic change was studied for different climatic scenarios. A look is taken at the catchment followed by the models applied and primary effects of climatic impact.