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The inevitable computerisation and automation of shipboard propulsion systems has given rise to an increasing number of possibilities of improvements in its operation. The expert system developed for the diagnostics of the marine diesel engine conditions is based upon experimental data obtained by measuring the relevant performances of the shipboard engine and by continuously monitoring its operation. In this area the expert system has had an enormous impact on the use of computers elsewhere aboard ship. An optimum injection time has been achieved in a variety of operating modes by eliminating the camshaft and replacing it with a high-pressure VIT (variable injection timing pump). The VIT pump's various parameters can also be easily adjusted during engine operation to achieve optimum performance. A conceptual solution concerning VIT pump operation is sought by means of the expert system to determine an optimum angle of fuel injection. The results of imulation presented here clearly justify the use of such a system aboard ship. The fuel injection control sub-system is part of the entire shipboard propulsion system. It can make a significant contribution towards a better understanding of the functioning of other operating systems which makes it particularly suitable to be included in the marine engineering teaching curriculum primarily the courses dealing with marine engines.

Many high-speed displacement or semi-displacement marine vessels are designed with transom or cutoff sterns. The reason for choosing such an apparently unstreamlined form is subject to debate. An extensive set of experiments on a transom-stern ship model is described. The geometry of the free surface of the hollow in the water behind the model was measured for a large number of cases. This data has been recently re-analysed and a new regression formula for the progressive un-wetting of the transom has been developed. This formula takes into account both the transom beam-to-draft ratio and the Reynolds number. There is evidence that the Reynolds number plays an important role in this process. A similar regression equation has also been developed for the length of the transom-stern hollow. Using these two new formulas one can now predict the resistance components with greater confidence. Hence the total resistance of a high-speed vessel with a transom stern can be estimated accurately over the entire speed range. This theoretical approach is validated against resistance data for a longitudinally staggered catamaran. Future work directed towards a CFD (computational-fluid dynamic) study of the transom-stern flow is identified.

Deep-sea oil and gas fields can only be exploited by improving all involved components simultaneously. Steel structures are a vital part of this challenge so two recent steel developments directly linked with deep-sea extraction are considered. Going deeper means switching to new platform concepts such as the 4th generation TLPs (tension leg platforms) with stepped tendoners which will in the future attain depths of 5000 to 10000 feet enabling new and promising oil and gas fields to be reached. TLP platforms are connected to the seabed by strings of tendon pipes. For such water depths X70 pipes with a wall thickness up to 1.5 inches. (40 mm) are required. The demands put on steel pipes for tendons are different from those of riser pipes since they are subjected to longitudinal extension stress and hydrostatic pressure instead of internal pressure which means a different set of mechanical properties for steel plates and pipes. Of course high toughness values and proved weldability complement this profile. In order to fulfil those requirements a new specific steel grade with adjusted analysis and production route has been designed by Dillinger Hutte GTS in co-operation with Europipe GmbH. The latest experience and production data is presented. More generally the access to deep-sea resources is conditioned by the development of high strength steels with excellent weldability. A recent step towards this goal has been the production of a S500M grade with very low carbon equivalent - not higher than for S420M.X17398

Natural gas represents a source of clean energy for which global demand is increasing. Over three-quarters of the world's known offshore reserves of natural gas remain undeveloped due to the high cost of transportation. These reserves are found in far-off and remote locations. Therefore a new flexible easy-to-implement natural gas transportation method is required. The development of CGL (compressed gas liquid) is described. CGL is an alternative natural gas transportation system for which patent applications are pending. The system does not require the low temperatures of LNG or the high pressures of CNG and avoids costly shore-based assets required for the liquefication and regasification of LNG. For CGL gas is loaded by offshore pipelines and SPM or CALM-type buoys connected to offshore pipelines for delivery to a land-based gas grid. The CGL storage technology is suitable for either a purpose designed new built vessel or a conversion of existing tonnage particularly single-hull crude oil tankers facing phase-out. The gas is transported in liquefied form but production gas is conditioned aboard the CGL carrier and the neutral gas components (methane ethane propane and butane) are transported on the same gas carrier in liquefied form. The resulting volume is equivalent to about two thirds of LNG. The liquefied gas is transported at modest pressure and refrigeration temperature in a pipeline system mounted within the cargo area of the gas carrier. The technology and tanker design are discussed.

The new generations of diesel engines require a lube oil filter concept which meets the demand of finer filtration for the different lubrication points in an engine. Even if the quality of the oils has been adapted to keep all parts free from sediments and to minimise wear today not only the filter fineness should be considered but also how wear is mainly caused by the number of solids which pass the clearance of bearings and flow with very high velocity inside the hydraulic valves. The so-called cleanliness level of an oil system and the retention rate of the used filter mesh are the most important parameters for a maximum lifetime of the affected engine components. Comparisons of different filter media are presented and to what extent the valid ISO standards can be useful to compare the different solutions offered by the filter manufacturers. The questions considered are: whether one filter is sufficient for the safety of the bearing; how it ensures a long lifetime; and whether it is more economical to split the oil system to filter the oil according to the demand of the bearings turbochargers hydraulic pumps and valves. Boll & Kirch has equipped RT-Flex engines and MAN B&W ME engine with 6 and 10 micron filters. For a reliable system all filters installed: the main lube oil filter and the turbo charger filter and the hydraulic filter have to be evaluated by means of multi-pass testing or measurement of the mesh size. The balance of a well-performing lube oil system does not only depend on the filters although they do play a major role in the reliable operation of the propuX35998

In 1996 coldwater investigations at the US NMRI (Naval Medical Research Institute) in Bethesda Maryland demonstrated the inadequacy of existing diver thermal protection for combat swimmers in long-duration cold water missions. To address this deficiency by supplementing the insulation of divers' dry suits a suit liner system containing super-insulating aerogel materials is being developed. In 2005 the US NEDU (Navy Experimental Diving Unit) in Panama City Florida carried out a repeated measures series of 12 test dives each up to three hours in duration to compare the thermal performance of a prototype diving garment using a super-insulation aerogel fabric with that of a commercially available Thinsulate garment worn beneath a commercial dry suit. The thermal benefit of the experimental aerogel garment was determined by statistics describing psychological and physical thermal status data from the aerogel and the commercial Thinsulate garments. All tests were carried out to simulate long-duration cold-water conditions in the NEDU test pool where water temperature was maintained between 1.7 and 4.4 degrees C (35 and 40 degrees F). Divers remained immobile while either lying or sitting in chairs on the bottom of the test pool and they subjectively reported their thermal comfort at 30-minute intervals during each dive. Mean dive durations were found to be approximately 43 percent longer when divers wore the prototype aerogel garment than when they wore an M400 Thinsulate liner. The prototype aerogel garment also enhanced thermal protection to the fingers and toesX27293

Int symp held April 30 - May 2 1986 in Louisana USA Papers are Air Expendable oceanographic instruments Marine application of argos An overview of remote sensing technique for ocean application in China Oceanography from space - the TOPEX/POSEIDON mission Real time acquisition and interactive image processing of oceanographic satellite data Spatial and temporal statistics of significant waveheight and wind speed as measured by the GEOSAT altimeter Directional wave data acquisition and preprocesssing on remote buoy platforms Moored and drifting buoy data processing at NDBC - collection analysis and archival NDBC wave data products - present and future An evaluation of the WMO non real time marine data exchange system An archiving and analysis system for geophysical data A software package for processing conductivity temperature depth data Use of principal component methods to produce and compare large sets of hindcast and observed wave spectra Initiating an Arctic SOFAR programme Lifespan of Arctic data buoys Coast of California storm and tidal waves study - Observations from the San Diego region directional wave data network Cost 43 drifting buoy programmes Development of an operational mooored buoy network An ocean dumping surveillance system The Draper profiling current meter - A self contained open ocean profiler The ARE digital thermistor chain An advanced water sampling system for in situ concentration of trace compounds from water In situ sampling/concentration for hazardous ica chemical analysis in the marine environment VARIOSENS - a versatile in situ flurometer for fast measurement of fluorescent tracer substances Bioluminescent photometer system - hardware and capabilitiX47072 MDV 3000 JUPITER Service flexibility and profitability V Farinetti

Fishermen have the highest occupational risk of death and injury of any occupation in the United States. The main concern lies with vessels of less than 40 foot in length. Methods are being developed for the real-time assessment of ship stability with practical application to safety monitoring and early-warning instrumentation. Ship motion is reviewed together with the background of current models describing roll motion. The characteristics of the five craft used in this study are described. New instrumentation for measuring the kinematics associated with small vessel roll is described. An instrument for measuring and recording ship roll is presented on based semiconductor accelerometers used singly or in a linear array. The measured roll behaviour is presented for the five craft with different loading conditions. Two sets of experiments are carried out with six craft in a variety of sizes. Implications of the experimental results are subsequently discussed. The first experiments show that there is significant shift in the roll axis from the centre of gravity which is attributed to interaction with sway and pitch. The second experiments show that the change in BG accounts for most of the variation in roll period with different weight distributions. This is attributed to an intrinsic correlation between ship parameters and the shift in roll axis. A detailed analysis of the instrument response and methods for locating the roll axis are given in an appendix.

SHOALS (Scanning Hydrographic Operational Airborne Lidar Survey) operations have been used for some eight years and have proved that airborne lidar is an ideal tool for rapidly measuring shallow water depths. More recently SHOALS data has ben merged with hyperspectral imagery to provide such valuable information as bottom typing in Sarasota Bay and Biscayne Bay in Florida. Hyperspectral imagery was identified at a recent airborne hydrography workshop as a complement to SHOALS data collection for the quantification of water column properties like sediment concentration and identification of navigation hazards. Current research focuses on using hyperspectral imagery with SHOALS data to help accurately delineate the land-water interface. A new lidar system called SHOALS-1000 is presented. This is being developed to advance the data fusion effort by allowing topographic and hydrographic lidar to be flown from the same platform as a hyperspectral imager. An overview is presented of past and present efforts which aim to: fuse SHOALS airborne lidar bathymetry with spectral imagery; identify additional uses of hyperspectral imagery for airborne hydrography; and describe the advances in airborne lidar technology that will allow concurrent collection of topographic and hydrographic lidar and hyperspectral imagery.

a new model of a marine shafting is established in this paper in order to calculate dynamic bearing reactions. In this new model the hydrodynamic excitations of propeller the characteristics of the oil films of bearings and th rigidity of the pedestal-hull system of a specific type of ships are taken into cosideration. The modeling process of the marine shafting is as follows: Firstly the rational alignment model of the shafting is set up and the relativestatic reactions of the shafting bearings are calculated. Secondly the static and the dynamic rigidities of pedestal-hull system are calculated based on the finite element model (FEM) of the stern part of the ship and the bearing forces of the hydrodynamic excitations of propeller are also calculated according the wake data obtained from model tests. Thirdly the FEM of the oil films of shafting bearings is developed according to the Renault Equation in order to obtain their dynamic characteristics. The new dynamic model of the marine shafting is established. In order to verify the new model the movements of the shafts centers at three definite shaft sections are measured during the sea trial of the vessel and the test results are compared with those calculated theoretically according to the new dynamic model. It is found from comparison that the new dynamic model is credible.

Echoes from patches of fish fluctuate significantly from ping to ping as the sonar beam is swept across the patches. The fluctuations can be strongly non-Rayleigh because 1) there can be a small number of targets in the beam at a time 2) the distribution of fish can be inhomogeneous or 'patchy' and 3) the echoes are weighted by the non-uniform response of the sonar beam. Two distributions have previously been identified which describe the statistical behaviour of non-Rayleigh echoes from fish - the K-distribution for patches of multiple unresolved fish and a power law distribution for individual resolved fish. The K-distribution has been shown in previous studies to describe the statistics of targets with a Gamma distribution of echo amplitude. The power law distribution is based on the method proposed by Ehrenberg et al. for circular aperture transceivers where a more general physical interpretation to the K-distribution is provided and a generalised power-law distribution to include beam pattern effect is developed. In addition the data collected in the 2-10 kHz range with Atlantic herring are compared with the model predictions for two types of groupings of echoes -- within patches and across patches.

In recent years demands for transportation by ship have increased and there has been a demand for improved ship fuel efficiency due to environmental problems and increasing crude oil costs. For a tanker or a bulk carrier enlarged in the current design trend wind drag is expected to increase. Therefore the importance of design and technology for wind drag reduction is increasing. In order to investigate the wind drag reduction mechanism generated by a corner cut and a step-shaped design in the accommodation tower of a ship LES (Large-Eddy Simulations) of turbulent flow around the simplified models of accommodation tower are carried out. The results of the numerical simulations are compared with experimental measurements for a validation. The predicted reduction rates of wind drag in each model are in good agreement with the measurement. The visualised flow structures from the simulation results show cavity flows in the cut corner and the step. Such cavity flows can make the flow around the accommodation tower smoother than before and the wind drag can be reduced. The LES of the simplified models is carried out using hull geometry and the interactions between the flows around a hull and its accommodation tower are also discussed. In a crosswind condition with certain yaw angle the wind separates at the side edge of the hull. In this case the wind does not impinge on the lower level of the tower and wind dr90515

Petrels and albatrosses have an excellent sense of smell and routinely navigate over the world's oceans by mechanisms that are not well understood. Several recent studies have shown that a number of procellariiform species do not require magnetic cues to navigate over the open ocean suggesting the involvement of other sensory modalities. Since it is now well established that procellariiforms and burrow nesting species in particular rely heaving on olfactory cues for both foraging and nest relocation investigation is presented here into whether olfactory cues may also be used for orientation in other contexts. It has previously been suggested that DMS (dimethyl sulphide) may be an odour cue birds use for navigation in part because emissions reflect bathymetric features such as shelf breaks and seamounts. These features suggest an odour landscape that may provide birds with navigational information over a seemingly featureless ocean environment. DMS is produced by phytoplankton and emissions increase during zooplankton grazing. We have previously shown that seabirds are attracted to high source concentrations of DMS within a foraging context. Here we present the first physiological data demonstrating that unconditioned birds can detect DMS at biogenic concentrations.

Herring and sprat together formed approximately 90% of the prey of Baltic salmon feeding in the eastern and southern parts of the Baltic proper in samples collected from 1995-1997 although there were spatial and seasonal differences. Salmon have probably increased their feeding on sprat. It has been proposed that the rising frequency of the M74 syndrome is associated with the increase in abundance of sprat which have been supposed to have a high thiaminase activity that would result in an inadequate supply of thiamine for salmon. Thiamine deficiency has been connected with the M74 syndrome. There could be differences in thiamine content between herring and sprat. The aims of this study are to determine the PCB PCDD and PCDF congener and thiamine concentrations in sprat and herring sampled from 1994-1995 when the M74 mortality of salmon yolk-sac fry was high. A look is taken at materials and methods covering fish samples/preparation of homogenates analysis of organochlorines thiamine analysis and statistical analysis. This is followed by results and discussion of thiamine organochlorine levels and organochlorine bioaccumulation.

Pipelines in particular oil and gas ones are often subjected to heavy lateral loads which may cause significant damage. The ability of pipelines to absorb the applied load energy and transform it into plastic deformation is of particular interest in numerous practical engineering applications. Here the focus is on the denting the response of pipeline segments subjected to lateral quasi-static wedge loading in the presence of internal pressure. Non-linear finite element models of pipeline segments which are in good agreement with denting test data from internally pressurised pipes are used to obtain load-deflection curves for different levels of pressure for various wedge shapes and for different types of boundary conditions. It is found that the presence of internal pressure increases significantly the denting resistance. This study emphasises the development of a simplified 3D-analytical model which yields closed-form expressions for the denting force and the corresponding denting length in terms of the corresponding denting displacement. The model introduced elsewhere for non-pressurised tubes is enhanced to include the pressure effects accounting for different types of pipe end conditions. The analytical solution compares very well with the finite element results and illustrates tube-denting response in a clear and elegant manner.

One of the main causes of deterioration in pipeline systems used by oil industry is the corrosion. Non-destructive inspections identify corrosion damage and provide information for future inspection and maintenance strategies. However inspections are expensive and are therefore undertaken at period of several years. The inspections only provide partial information. A reliability model is presented for determining the pipeline safety after obtaining information on the corrosion damage of the piping system by non-destructive inspection. The model is used to estimate pipeline system reliability in every region containing detected corrosion defects and the probability of either global system failure or of a given pipeline segment. The global failure probability incorporates the contribution of defects that are undetectable by the inspection tool. For this the probability density functions of maximum depths and the number of undetected corrosion defects by the inspection tool are also determined. The failure associated to each corrosion defect is determined from the pipeline resistance and fluid pressure. The model is applied to a pipeline segment of a given length showing that defect measurement errors and the contribution of corrosion defects undetected by inspection tool can significantly influence the value of failure probability of the system. To calculate the failure probability of the system the directional simulation technique is used.

The CEM (Macau Electric Company) has a power generation asset mix consisting of medium- and low-speed heavy fuel oil fired stationary Diesel Engine generators two heavy fuel oil fired boiler-steam turbine generators and a combined cycle power plant running on distillate (diesel oil). Total installed capacity of CEM in Macau as at December 2006 is 488 MW. A decision was taken late in 2002 to tender for the refit of an SCR (selective catalytic reduction) system and other engine improvements onto each one of the six Diesel Engines with the aim to reduce particulates and NOx emissions to levels consistent with international best practice. The adverse environmental problems faced in the early stages of the operation of the SCR system as installed are discussed. These were caused by unexpected and unacceptable plume fall out and visibility impacts onto the surrounding areas of the plant. A number of plant adjustments involving a different type of catalyst fuel quality manipulation and innovative and untested plume abatement equipment options with the potential to reduce or eliminate the visibility impact were investigated with direct involvement of the original SCR system designers and suppliers.

The mission of NAVOEANO (the Naval Oceanographic Office) is to conduct multidisciplinary military ocean surveys collect and analyse oceanographic data and generate operationally significant products and services that address Navy and Department of Defense oceanographic needs as well as those of academia and civil agencies. NAVOCEANO provides near- real-time and long-term oceanographic product support in the form of text graphics remotely sensed products and databases. NAVOCEANO constitutes a production environment for analysing oceanographic features from in situ data imagery and databases and for producing tailored and standard products for a myriad of operational customers. Production can consist of automated processing database creation or scientific analysis of various data sets. To track the requirements and requests for products from receipt to dissemination the production process has been captured in a workflow software package called FLOW (forward looking office workflow). A system is described designed to meet production management requirements for operational products at NAVOCEANO. The current use of the FLOW software and an initiative to integrate FLOW into the hydrographic production process is described. A link will be made between the FLOW software and a COTS (commercial off-the-shelf) performance management software PBViews (panorama business views) to give an office-wide perspective on production management and performance.

The SCP (sand compaction pile) method is the most common compaction method for ground improvement in Japan. It is used to treat all types of soft grounds ranging from sandy to clayey by compacting and consolidating the ground's drainage and using natural clean sands as a filling material. In this paper laboratory tests are carried out on a range of artificially adjusted materials equivalent to construction surplus soils (sands intermediate and clay soils) to evaluate their applicability for recycling as a filling material in compaction pile methods such as the SCP method. The relationship between gradation as a material property and plasticity index is examined as a factor influencing compaction characteristics as well as shear and permeability characteristics. Results are presented. It is concluded that the conventional quality regulations of a fines content below 15% is not suitable for filling material in the compaction pile methods such as the SCP method. A range of materials that are non-plastic or of low plasticity can be used regardless of their fines content. Thus the scope for using recycled materials as filling material extends to cover non-plastic or low-plastic sandy or fine soils.

The cheapest and safest place to store gas is inside a reservoir. Over the years Gaz de France has developed unique expertise in this field. A brine-filled reservoir is used to store imported gas during the summer and pump it out in the winter according to domestic demand. In this context the monitoring of bubble expansion field pressure and gas saturation is critical to optimise field management and gas recovery. Several seismic monitoring experiments have been carried out over the Cere-la-Ronde test site with varying degrees of success. Right at the beginning of the reservoir filling in 1993 a baseline walk-away survey was shot using permanent down-hole geophones. From then until 1997 five repeat surveys were shot with the same configuration and the same vertical PDG antennae. The seismic data were optimally processed. Travel times and impedance variations in the reservoir vicinity correlated with the gas volume as it increased and decreased aver the period. This technique allowed the bubble extension and its contraction to be followed on a discrete basis and the changes in the reservoir properties to be tracked.