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Recreational boating in the US has undergone tremendous changes during the past 50 years both quantitatively and qualitatively. The number of boat registrations has increased together with the type of boats and the boating activities. There are basically two reasons why these developments have resulted in a demand for new and more relevant navigational charts and other aids to navigation. Firstly the nations Small Craft Navigational Charts should reflect the diversity of boating activities which require additional information that is generally not readily available on the charts developed and distributed by NOAA's Marine Chart Division. Secondly and perhaps more importantly the increase in the number of boats has begun to stress the coastal and near-shore marine environment. Examples of this include increased manatee mortality sea grass scarring discharge of waste materials overboard (although this is now prohibited) increased powerboat speeds inappropriate anchoring practices. An initiative is reported to identify the information that small-craft charts can convey to enable safe navigation and to promote environmental stewardship. The methods and findings related to the following two project objectives are discussed: to determine whether additional chart information would result in increased safe navigation and environmental stewardship; and to determine whether chart information needs vary with the type of boat owned and the respondent's education.

The wedge wave-make is and has been a topic of interest to hydrodynamicists. The analysis of the performance of a wedge-type wavemaker in a tank of finite depth is presented. The analytical technique is somewhat different to those applied previously to performance studies of wave-makers. Those techniques included the assumption of a product solution of the Laplace equation which lead to combinations of sinusoidal and hyperbolic functions of the wave number. In the technique described here both product and summation solutions are assumed. This assumption is based on the fact that the fluid beneath the wavemake is confined by the wave-maker the back wall and the tank floor. From potential-flow theory the streamlines of the oscillatory flow of this confined fluid are well defined. In a 3D analysis of hydrodynamic coefficients of a heaving vertical circular cylinder Yeung (1981) makes this assumption without stating so. Using the experimental data of Wang (1974) for comparison results of the analysis are presented for various combinations of wave-maker draft breadth and water depth for a triangular wedge. The results show that the effects of the evanescent waves are of second-order. Close to the wedge results are presented resulting from the inclusion of four evanescent waves. The technique is of value because of its relatively simple form and its versatility.

The Snorre TLP has been operating in the Northern North Sea since 1992. During the last year an extensive reanalysis of tether tension TLP motion and airgap has been carried out in order to ensure that the TLP can withstand updated environmental conditions and design requirements. The aim of this paper is to describe the analysis methods which have been used to determine extreme tether loading and to compare analysis results with model test results. The model tests were carried out in the facilities at MARIN in the Netherlands and considered more than 200 three hour realizations of irregular seastates with and without wind and current. Typical fatigue seastates as well as extreme 100 year and 100000 year seastates were investigated for both head and quartering seas. The extensive database of model test results gives an opportunity to study the accuracy of the analysis methods. The analysis of the TLP response was carried out in the time domain using the SIMO software developed by Marintek. In the work described here the results from a purely linear radiation-diffraction analysis is used as the main load model in SIMO together with slender element additions based on the incident wave kinematics.

The accuracy and resolution of sediment bulk density measurements are examined. Bulk density from cores is traditionally measured by weight loss of extruded and sectioned 2-cm-thick sediment disks. The actual bulk density is thus an average value for the volume of a 2-cm-long-x-cross-sectional-area sediment core disk. Thus the values of the measurements as well as the estimates of the correlation lengths may be a function of the disk thickness (sampling interval) and estimation of correlation lengths may be distorted. From a bulk density power spectrum and correlation length estimated from existing data Monte Carlo realisations of the density were obtained for the sediment volume. From such realisations the same procedures used in the actual core analysis on the simulated cores were reapplied to obtain a 'virtual' bulk density profile and then re-estimated the power spectrum. Because actual density is known from the original data in the simulation the difference between the parameters used to generate the simulation and the 'virtual' parameters is a measure of the distortion. As a result of numerous simulations run to achieve a robust estimate of 'virtual' bulk density it is shown that laboratory procedures bias (lower) the actual variance of the parameters by averaging or smoothing. In related work however the first-order auto-regressive approach for estimating correlation length from contiguous disks indicates a bias toward a higher value of the parameter than is appropriate.

Today's MBES (multi-beam echo-sounders) provide detailed bathymetric information that allows local slope corrections to be made to the concurrently collected acoustic backscatter imagery thus improving seabed characterisation possibilities. Although the data is available local-slope corrections are not typically applied in the backscatter-processing scheme. An approach is presented that compensates backscatter for local slope by taking into account vessel yaw pitch and roll angles when determining the beam incident angle at the sea floor and using all the available closest neighbour soundings within a certain radius. The normal of the 3D local curvature at each beam location is then calculated by a weighted least squares fit to the surrounding surface. The proposed method can use all the available geometric information from co-registered depths and backscatter strengths either from a single survey line or multiple survey lines if overlapping lines exist. These grazing angle computations lead to estimates of the sonar's transmitting and receiving beam patterns and their deconvolution from the backscatter data to extract seafloor property information in regions of complex topographic relief. This technique is applied to a backscatter image created from data collected on the mid-outer continental shelf off the New Jersey Margin with a Simrad EM100 multi-beam sonar system. Backscatter data normalisation with the computer grazing angles yielded a better correlation between the independently measured grain size and backscatter data than that obtained with non-normalised backscatter data. 87933

Ideas from using bio-inspired locomotion concepts for robotic underwater applications are presented. The technology of land-based bio-inspired walking robots has improved a lot in the last ten years. For example systems like The SCORPION Rhex or DANTE II have proved that high mobility in rough terrain can be achieved. Walking is a locomotion technique that can be found in underwater animals such as lobsters crayfish or prawn. These animals can be found in the littoral zone of the oceans and rivers which is a very challenging environment. Crayfish and prawn can also live in rough terrain like the slope of a black smoker. They are especially able to adapt to irregular ground contours currents wave action and surge. For example lobsters can navigate around obstacles such as rocks crevices and seaweed. They flourish in the benthic and littoral environments and have developed robust control systems for locomotion sensing and searching behaviour. These control systems therefore present a solution. No artificial wheeled or swimming system is able to navigate as robustly as lobsters or crayfish in such underwater environments. Studying the behaviour of animals in the littoral zone and using their control principles for robots would seem to be a promising way to close this gap. Past research in this direction was analysed (for example the ARIEL and the NEU Lobster project) and new ideas based on our existing systems are proposed for a robust underwater walking platform. A possible control concept for such an underwater walking system is proposed. Possible application scenarios are discussed100285

Epizootics of cancers and other neoplasms in fish have been reported from various countries since 1941. Some of these instances have shown a viral etiology. However many have been associated with chemical carcinogens particularly PAHs (polynuclear aromatic hydrocarbons). In North America alone PAHs have been implicated in 23 tumour epizootics involving 11 different species of freshwater and marine fishes. The species most commonly involved are benthic omnivores in contact with PAH-rich sediment and feeding on contaminated benthic invertebrates. Analysis of invertebrates provides PAH profiles similar to those in sediment and the presence of PAH in bile metabolites demonstrates fish exposure. Many of the studies have come from industrialised tributaries and embayments to the Great Lakes or coastal areas where point sources such as creosote or coking plants were established in past decades. The case of the Black River Ohio in the 1980s is described. The lower reaches of this river have been greatly influenced by steel and coking facilities for decades. Brown bullhead Ameiurus nebulosus a common benthic-feeding fish in the system was surveyed for pathology particularly liver tumors (both hepatic and biliary). The results are described. Remedial dredging of the river was carried out in the 1990s. The results are presented.

Acoustic detection and classification of buried or proud sea mines presents a very challenging problem. This study introduces a new feature extraction method for detection and classification of buried underwater mine-like objects. Multiple sonar returns off an object are used where each sonar return is characterised by its specific frequency subbands which contain valuable discriminatory information that can be used to correctly determine the type of object encountered. Features are extracted from the data using CCA (canonical correlation analysis) between the selected frequency subbands of two sonar returns and are subsequently used to classify mine-like and non-mine-like objects using a simple classifier. This method offers a more rigorous way of performing acoustic colour processing where ping-to-ping coherence between sonar returns is also exploited in extracting acoustic colour features. This method is tested against a previously developed time domain multiple-aspect feature extraction method on a database that contains sonar returns from various buried or proud mine-like and non-mine-like objects in different operating and environmental conditions. Results are presented in terms of the ROC (receiver operating characteristic) curve for each system and overall detection and classification performance in different operating and environmental conditions. The recently collected BOSS data set and its properties are described as well as the pre-processing steps necessary for extracting coherence-based frequency subband features. The frequency subband coherenX15059 The BURL guide to the Control of Substances Hazardous to Health Regulations 1988

NOS (NOAA's Ocean Service) CO-OPS (Centre for Operational Oceanographic Products and Services) manages a Current Observation Program with a main objective of improving the quality and accuracy of the annually published Tidal Current Tables. The dissemination of tide and tidal current predictions is a critical part of NOS' efforts toward promoting safe navigation in our Nation's waterways. A field test of a streamlined sub-surface mooring buoy containing an acoustic Doppler current profiler was carried out in the winter of 2001-2002 at the entrance to Delaware Bay. Time series of pressure tilts and heading were analysed to track the behaviour of the mooring in the tidal current. Current measurements collected in a standard bottom-mounted platform served as a reference in assessing the quality of data collected in the mooring buoy. Tidal analyses were carried out on both datasets. A comparison of several analysis products including tidal constituents tidal current predictions and Greenwich intervals suggests no significant data degradation due to the sub-surface mooring dynamics. In these conditions the SUBS mooring buoy system proved to be a good alternative to the standard bottom-mounted platform. Test results show that the SUBS mooring is potentially a very useful tool for CO-OPS' Current Observation Program. In the light of these positive results NOAA's Ocean Service will begin to routinely use streamlined sub-surface moorings when appropriate for tidal current surveys.

The Royal Navy's future aircraft carrier (CVF) HMS Queen Elizabeth will be the world's first aircraft carrier to adopt an IEP (integrated electric propulsion) system and one of the largest and most powerful electrically propelled ships in the world. CVF will also be the first electric ship for the navy designed to be so from the outset without any mechanical legacy constraints. The design has been some 10 years in the making and along the way there have been many twists and turns in the technical and commercial areas that have driven the technical solution. Here some insight is given from a power and propulsion perspective of where the carrier has come from and where she is now and where she might go in the future as we stand on the edge of the manufacturing phase. It is outlined how the current all-electric power and propulsion solution is proven but innovative capable but prudent and graceful rather than redundant. After a period of competition value engineering military and commercial equipment evaluation both the power and propulsion design and team is fixed and moving forward in a co-located alliance structure for the first time.

One of the Computational Technology Areas supported by HPCMP (the high-performance computing modernisation program) is CWO (climate weather and ocean) modelling. To this end state-of-the-art computing architectures are leveraged against the extremely difficult problem of mathematically modelling and predicting the behaviour of a variety of ocean climatological parameters. The problem is that the technology to store retrieve manipulate and display these data has not kept pace with the computational technology. NAVO MSRC (the Naval Oceanographic Office Major Shared Resource Centre) Visualisation Centre is challenged with providing its users with state-of-the-art analysis environments for the interrogation of their increasingly large data sets. This paper deals with the data generated by the CWO community all of whom work with large domains and high resolutions that vary over time. This leads to very large data sets for each time step and can challenge even the most powerful architectures when trying to extract or 'mine' information from the raw data. As in most visualisation applications the model output deals with physical parameters that are invisible to the naked eye. This means effective methods of display are required for ocean circulation or currents sea surface height temperature salinity and so on. Data mining is overviewed. The technical solutions that were built to solve the challenges described above including algorithms data descriptions and formats are dealt with. Future work is considered.

Marine sediments often contain substantial quantities of dissolved gases or methane clathrate hydrates. Clathrate hydrates are a combination of methane and other low molecular weight gases and water molecules into a substance similar to water ice that occurs at the relatively low temperatures and high pressures found in the deep ocean. Recovery of cores containing hydrates is often problematic because of the rapid decomposition of the hydrates and the very large gas expansion that occurs due to the great reduction of pressure as the sample travels up to the sea surface. In the past recovered clathrate samples have dissociated partially or completely by the time they reach the sea surface. In order to preserve and experiment samples they must be held at pressure and temperature conditions below their phase change boundary. This requires the sampling equipment and the sample storage facilities to be specially designed to preserve these conditions. A hydraulically actuated pressure-case is described which has been developed to recover intact samples of methane clathrate hydrate and gassy sediments from the sea floor. This system can be used on any submersible or ROV that has hydraulic control lines available for user mounted devices.

NGS (the National Geodetic Survey) is a programme office within NOAA (the National Ocean Service of the National Oceanic and Atmospheric Administration). It is charged with providing shoreline and associated data for mapping the US's 95000 miles of coastline. The RSD (Remote Sensing Division) within NGS carries out photogrammetric surveys to photograph and when prioritised compile shoreline and associated data for application to the Office of Coast Survey's nautical charts. The update cycle for a nautical chart varies from 6 months to 12 years depending on such factors as the rate of cultural and natural changes. This shoreline data is available to the coastal GIS community through the National Geodetic Survey Shoreline Data Explorer website. CSMAP (The Coast and Shoreline Change Analysis Program) is managed by NGS and acquires contemporary high-resolution imagery such as 2 meter SPIN2 orthorectified imagery and 1 metre IKONOS non-orthorectified imagery to detect shoreline changes when compared with nautical charts and to evaluate ports. The imagery is accurately geo-referenced and compared with the nautical chart to detect changes. The analysis of these discrepancies is used to determine which ports or areas within a port require expensive photogrammetric survey mapping. The CSCAP procedure is described and future activities are outlined.

Modern two-stroke exhaust valves operate under extreme conditions and are therefore a cost and service intensive part of the engine. Combustion deposit-induced wear on the valves and seats currently forces most operators to service their exhaust valves after 6000 to 8000 hours. MWH (Markisches Werk GmbH Halver) has designed the 2-stroke ReliaValve with Sentry Rotator to increase TBO (time between overhaul) to 18000 hours and to provide predicable service intervals. This mechanical rotator the Sentry Rotator can be incorporated into existing exhaust valve assemblies with minimal modifications and provides positive rotation of the valve spindle during the closing movement. Application of the Sentry Rotator addresses the two main wear mechanisms in 2-stroke exhaust valves (adhesion and abrasive wear and build-up of deposits and dent marks) thereby extending the service life of these components. An engine field test program has resulted in some refinements to the rotator design and ultimately in a well-proven product. Results obtained thus far indicate that a TBO of 18000 hours and beyond for 2-stroke exhaust valve assemblies will be achievable. The rotator design addresses the typical wear mechanism of 2-stroke exhaust valves and considers the tribology thermal loading mechanical loading

Microbiological water quality of the coastal zone is currently determined by using bacterial indicators to infer the presence of microbial pathogens. However the use of bacterial indicators is limited in that they sometimes fail to successfully predict the presence of all types of pathogens. Also bacterial indicators are not always a useful predictor of the presence of human fecal contamination. In the 10 years a number of new molecular and microbiological techniques have been applied to the field of coastal water quality. These techniques have largely been used to provide further information on the presence of pathogens and-or to separate sources of fecal contamination as either 'human' or 'non-human'. Some of these methods offer rapid and reliable results and might in the future be useful for day-to-day management decisions. Some of the methods are 'database oriented' where a watershed's fecal contamination sources are characterised over a period of time in order to provide information for mitigation actions such as TMDLs (total maximum daily loads). All of methods are research methods and are constantly being changed and improved to increase accuracy sensitivity and rapidity of results. Some of the methods being currently used to identify sources of fecal contamination are introduced and reviewed. These include: ribotyping PFGE (pulse field gel electrophoresis) PCR (polymerase chain reaction) RT-PCR (reverse transcriptase-PCR) Q-PCR (quantitative-PCR) determination of ARP (antibiotic-resistance patterns) and F-specific coliphage analysis. Each met99495

Traditionally rubble-mound or rock revetment has been an accepted method of coastal defence but the supply of rocks is limited and the method is less environmentally friendly. Alternatively various types of articulated block have been designed and prefabricated in the form of pre-cast concrete blocks. These blocks provide a higher stability coefficient value compared to rocks thus allowing the use of a lighter weight of the blocks as well as provision for additional design features that can provide the strength against the impacts of the waves current and tidal changes. The development of a new revetment system is reported. The Sine-Slab system is uniquely designed to work with nature's forces. It is effectively stable and durable against hydraulic loading at the same time as being effective in trapping sediment aesthetic and environmentally friendly. Hydraulic model tests were carried out at various model scales and variable parameters. Simulation tests for stability and run-up were also carried out for guidance in the detail design of a Pilot Project. Field tests and monitoring work have been carried out to check on the performance of the system and to prepare for future design guides. Results for the pilot project as well as the first and second commercial projects are encouraging. Continuous R and D is being carried out for the design and product improvement to facilitate production material composition and durability economic factors and environmental outlook.

In order to accomplish a production system with high efficiency in shipbuilding it is important to control the accuracy of blocks that are parts of a ship. When they are welded deformation will surely occur. So it is necessary to establish an accurate method for estimating the welding deformation. Studies were surveyed of a welding deformation estimation method that had been carried out in the past and some fundamental experiments on simple joints welded by methods actually used in shipyards were undertaken. The database for welding deformation was established and the relationship between the welding deformation and the weld heat input was formulated. Once the relationship between the welding deformation and the weld heat input was obtained the formula was applied to the welded structures by two methods: the simple method and the elastic finite element method. The welding deformation of the structures was then estimated. In order to confirm the validity and accuracy of the estimation method an experimental block that had a few curved members was produced. The experimental block was a modelled VLCC square body block and the deformations were measured very carefully. The estimated values of the welding deformation by the developed methods were found to be in good agreement with the actual measurements. Having developed the welding deformation estimation method for square blocks in shipbuilding the research is now extending to the development of the high accuracy production system for curved blocks.

One of the most eco-friendly of all farming practices is the Pokkali paddy cultivation cum-prawn farming in the wetlands of the southwest Indian coast which relies on the symbiotic nature of prawn and paddy. After the paddy harvest the decaying stubbles of the paddy serve as food for the prawns and likewise the prawn excreta make the field fertile. Absolutely no pesticide or fertilizers are used in the fields. It is high time for socially and health conscious people to propagate the use of organic food and to encourage this farming practice to other wetland regions of the world. This farming a community-based coastal resource management with participation of women and children which is indeed healthier and more sensible moneywise needs to be encouraged to protect the coastal wetlands. This alternative income-generating programme contributes to improve coastal environments and to conserve the biodiversity of the ecosystem. After some introductory information relating to the coastal districts of Kerala and the objectives of the study a look is taken at the Pokkali paddy Pokkali cultivation practice prawn cultivation

There continues to be a reduction in the number of ship's crews and the multi-nationalisation of them is still in progress worldwide. In spite of this safe and reliable operation of vessels remains essential for everyone engaged in the shipping business. From an after-service point of view high-quality up-to-date engineering service is required for ship-builders and-or engine manufacture in order to solve customers' different kinds of operational issues. With these points as background MES has developed a maintenance system called e-GICS (electronic Global Internet Customer Support) which gives customers answers to any engine operational problem and diagnosis results of their engine's performance every 24 hours on the website. This system has four functions: firstly the electronic carte system which is an electronic diagnostic system to observe and check the engine operational condition at all times including the engine performance diagnosis function and remaining life diagnosis function for major parts and components; secondly the electronic document system which unifies and controls the engine technical information having an intelligent search function in the database; thirdly the Q&A System a system in which customers can exchange opinions with engineers for the prompt solution of the technical problems; and fourthly

As the oil and gas industry is building much larger LNGC than so called standard size and is also considering operation in partially filled condition a more accurate and realistic assessment method and criteria are needed. In the past a simple methodology has been used to define the load and strength of the containment system to evaluate the factor of safety of the system. To meet the new demand of the industry. ABS has developed a procedure for the strength assessment of a membrane type containment system based on the combination of numerical analysis and experimental study. This paper is to present the technical background of the analysis procedure. The method for determining the load and strength of an LNG containment system and the acceptance criteria are to be described. For load sloshing model test requirement and procedure to determine the critical load cases and test conditions using sloshing simulation are to be presented with experimental results. Strength side of the equation dry and wet drop test procedure and how these test results are used in the determination of realistic impact strength including the interaction between the fluid and containment structure and dynamic structure analysis utilizing dynamic material characteristics and structure damping. The analysis procedure to evaluate two main containment systems will be presented with a nexample analysis. Results are summarized in the conclusions and recommendations are made for further study.