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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.

The propulsion of Dutch Navy ships is predominantly by diesel (for LCF (air control frigates) or diesel-electric (for LPD (landing platform docks) and submarines). A new class of OPV (ocean-going patrol vessels) has a hybrid system. A new joint support ship related to the LPDs will also have electric propulsion. The debate about the merits of diesel and electric propulsion has led to an increasing share of AES (all-electric ship). The next step is AES with HTS (high temperature superconductivity) electric power generation and propulsion possibly in combination with other HTS systems like transformers and fault current limiters. HTS systems have geometric advantages as their size and weight is probably a factor 3 smaller than conventional equipment which is of great interest on board. Fuel efficiency is another important argument because of range and sustainability. A study was carried out to establish the fuel efficiency of diesel electric and HTS drive trains in the case of an LPD and OPV. Their design sailing profiles as well as an actually monitored sailing profile were applied to the three drive trains to compare the respective energy efficiencies. The results are presented. It is concluded that a set of various diesel generator sizes in combination with HTS generators and motors will be most efficient for both ship types.

The ESA (embedded suction anchor) is a type of permanent offshore foundation that is installed by a suction pile. The cross-sectional shape of the ESA is circular with its diameter being the same as that of the suction pile that is used to drive it into the seafloor. To increase the capacity against pullout three to four wings (vertical flanges) are attached along the circumference with equal spacing. During installation the ESA is attached at the tip of a suction pile and then driven as a unit with the suction pile by the applied reduced water pressure inside the suction pile. Once the ESA reaches the desired depth the suction pile is retrieved by applying a positive water pressure inside the pile and leaves the ESA permanently in the seafloor soil. The mechanism of suction pile installation is well described. The primary factors influencing the horizontal pullout capacity of an ESA include the loading point the soil type the embedment depth and the addition of flanges. An analytical solution is presented which is capable of estimating the horizontal pullout capacity of ESAs with the loading point anywhere along its length with or without the flanges. Validation of the analytical solution is made through comparisons with the centrifuge model test results. The results show that the horizontal pullout capacity of the embedded suction anchor in sand increases reaches its peak and then starts to decrease as the point of the load application moves downward. The effect of flanges on the horizontal pullout capacity is also found to be significant.

An AUV has been specifically designed to withstand the difficult environment in the Arctic and capable of collecting a variety of scientific data. This tool has the potential to replace capabilities previously supported by the US Navy SCICEX cruises which used submarines for measuring and monitoring Arctic oceanographic properties. Ice draft data was one important piece of data historically collected by the submarines that MBARI's AUV now has the potential to provide. This data has particular value to climatologists and Arctic scientists who are striving to evaluate the impact of global climate on the thickness and extent of the Arctic ice sheet. The basic AUV platform is described together with its performance during ice profiling missions. Present details about the science payload section of the AUV as well as specifications for the Ice Profiler ice profiling sonar are then presented. The modifications made to the system to support real-time ice sonar data acquisition and AUV operational decision-making are also presented. Finally the algorithms used to generate estimates of ice draft both in real-time and using post-processing software are outlined along with the presentation of the ice draft results from one the missions. Lessons learned and future plans for the ice profiling science payload are dealt with in the conclusion.

Systems of flexible lines and cables are frequently used in civil and oceanic engineering design. Recent activities in the offshore oil exploitation industry require new structural concepts using flexible lines (both mooring lines and risers). Such systems present increasingly complex configurations with dynamic non-linear behaviour. Therefore the use of efficient numerical solution procedures based on the Finite Element Method becomes mandatory for their analysis. The usual analysis procedure for flexible lines by the FEM is based in the calculation of an initial stable static equilibrium configuration in order to define the finite element mesh. Usually this configuration is obtained by the classic catenary equations. However in more complex problems these equations cannot be applied. Therefore the objective of this work is to present the use of a more general finite element approximation associated to dynamic relaxation algorithms. Such algorithms can be started from arbitrary configurations not necessarily in equilibrium. The resulting procedure is accurate and robust and avoids numerical problems such as the ill conditioning of the tangent stiffness matrix allowing the static equilibrium configuration to be obtained in an efficient way.

In the research field of sea-keeping qualities the short-term prediction method has been established on the assumption that the seaway can be considered as a stationary stochastic process. In actual ship operations however the ship motions in waves are regarded as non-stationary random processes because the ship's manoeuvres such as course and speed alterations change the encounter angle and encounter frequency with waves. The TVVAR (time varying coefficient vector autoregressive) modelling is applied to the cross-spectral analysis of non-stationary ship motion data. Introducing the instantaneous response a vector autoregressive model can be reduced to simple TVAR (time varying coefficient autoregressive) models for each ship motion and the required CPU time is effectively reduced. The TVVAR model and stochastic perturbed difference equations are transformed into a state space model. The vector-valued unknown coefficients can be evaluated and the instantaneous cross spectra of ship motions can be calculated at every moment. The results showed good agreements with one of the TVAR modelling and also with the SAR (stationary autoregressive) modelling analysis under stationary conditions. Furthermore the instantaneous relative noise contribution was also estimated using the TVVAR coefficients and illustrated how the structure of a spectrum changed according to the ship manoeuvres for the first time. Optimum order of the model and Akaike's information criterion were also examined for several changes of parameters. Moreover it is confirmed that the TVVAR modelling can estimate the instantaneous cross spectra and relative noise contribution ofX11884 Institute of Electrical and Electronics Engineers; Standard dictionary of electrical and electronics terms 3rd Edition.

The methodology for predicting sand production is in general constant across the industry. That is the determination of formation strength and field stresses and the application of them to a failure model. However the variety of models available and their applicability and accuracy can be confusing with the results not always representing what is experienced under production conditions. Here a more holistic approach to sand production prediction is presented. This not only uses numerical analysis but also includes a qualitative approach using geological information. With respect to the numerical analysis the determination of various parameters used in modeling sand production and their effectiveness for different reservoir and production conditions is discussed. An overview of the various tests considered useful in calibrating these parameters is also presented. The geological approach discusses the impact of mineralogical depositional structural and diagenetic factors which can impact on the propensity for sand but which are not fully taken into account by a purely numerical approach. The advantages and disadvantages of each of these aspects are presented and synergies identified between numerical and qualitative analysis. Case histories are presented which show that each of these methodologies