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With the growing use of autonomous and semi-autonomous platforms and the increased data flows in modern maritime operations it is critical that the data is handled efficiently across multiple platforms and domains. A semantic world model framework for hierarchical distributed representation of knowledge in autonomous underwater systems is proposed. This framework aims to provide a more capable and holistic system involving semantic interoperability among all involved information sources. This will enhance interoperability independence of operation and situation awareness of the embedded service-oriented agents for autonomous platforms. The results obtained specifically impact on mission flexibility robustness and autonomy. The framework presented makes use of the idea that heterogeneous real-world data of very different types must be processed by (and run through) several different layers to be finally available in a suited format and at the right place to be accessible by high-level decision-making agents. In this sense the presented approach shows how to abstract away from the raw real-world data step-by-step by means of semantic technologies. The paper concludes by demonstrating the benefits of the framework in a real scenario. A hardware fault is simulated in a REMUS 100 AUV while performing a mission. This triggers a knowledge exchange between the incipient fault diagnosis agent and the adaptive mission planner embedded agent. By using the proposed framework both services can in Semantic web holds promises for ocean observing needs

Semn held in Hamburg April 18 - 21 1978 Papers are The European ship repai r industry - current status and future prospects Ship operators view of repair facility requirements Hull loss prevention and mitigation Technology and ship operation En voyage repair and retrofits - the operators viewpoint Progress in classification society survey techniques Corrosion control Retrofitting vessels to comply with inevitable legislation Assessing and planning for drydocking requirements of a mixed tonnage fleet In water survey and afloat maintenance from the operators point of view In water maintenance - a classification society view point In water surveys maintenance and repair - the state of the art Application of low quality fuels in large bore diesel engines Aspects for future bunker fuels and their influence on engine performance Lubrication efficiency as means of reducing operation and maintenance cost Microbial infection of ships lubricants Control systems - availability maintenance and repair Monitoring and diagnostic system for four stroke diesel engines A look ahead in turbine maintenance Marine fuels and lubricants - towards 1990 Spares selection and procurement viewpoint from a ship operator Spares selection and procurement - viewpoint from original spares suppliers - viewpoint from "open market" spares supplier

Semn held in Hamburg April 18 - 21 1978 Papers are The European ship repai r industry - current status and future prospects Ship operators view of repair facility requirements Hull loss prevention and mitigation Technology and ship operation En voyage repair and retrofits - the operators viewpoint Progress in classification society survey techniques Corrosion control Retrofitting vessels to comply with inevitable legislation Assessing and planning for drydocking requirements of a mixed tonnage fleet In water survey and afloat maintenance from the operators point of view In water maintenance - a classification society view point In water surveys maintenance and repair - the state of the art Application of low quality fuels in large bore diesel engines Aspects for future bunker fuels and their influence on engine performance Lubrication efficiency as means of reducing operation and maintenance cost Microbial infection of ships lubricants Control systems - availability maintenance and repair Monitoring and diagnostic system for four stroke diesel engines A look ahead in turbine maintenance Marine fuels and lubricants - towards 1990 Spares selection and procurement viewpoint from a ship operator Spares selection and procurement - viewpoint from original spares suppliers - viewpoint from "open market" spares supplier

Several of the major navies around the world have chosen to tread the path of the AES (all-electric ship) concept for their new-builds. Electric propulsion has come back into the military limelight in the past 10 years. Although it has never really gone out of fashion conventional submarines staying true to this concept for over 100 years electric propulsion was last seen in its prime during World Wear 2 when the USA had over 50 such surface ships in its fleet. With the developments in electrical machines and semi-conductor technology electric propulsion is back and several nations in particular the UK USA France and the Netherlands have adopted this on their new-builds this time taking it a step further making electricity the principal means of distributing energy onboard thus creating and AEA (all-electric ship). The new-builds that have adopted AES are mostly larger ships such as destroyers and carriers. But the AES concept is also a good solution for smaller ships and Sweden is one of a few countries exploring this idea. It has undertaken studies which demonstrate that the AES concept works well when applied to corvettes and boats. The advent of electrical weapons and armour makes it even more important to develop the small AES. Here insight is given into the efforts of Sweden (a small country with a limited budget) in the area of small AESs.

In shallow tropical and subtropical waters the ambient is often dominated by biological noise from snapping shrimp. This noise can severely limit various acoustic devices. There are other applications that rely on this noise as an incoherent signal for imaging. An opportunity exists to measure these characteristics with existing horizontal arrays designed and used for other purposes. Arrays that are designed for low frequency operation but that record data up to a frequency of 1 kHz or more are well suited for this purpose. They can potentially provide very high- resolution images of sound sources close to the array because of their length. The potential is explored of using broadband fully focused beamforming with such arrays to localise nearby shrimp snaps in space and time. Depth of field and cross-range resolution for typical arrays are calculated. These expectations are compared to data taken in the Timor Sea with a multi-frequency towed array in a water depth of about 100 m. The data clearly contains impulsive noise highly suggestive of snapping shrimp. Fully focused beamforming can clearly identify individual snaps and localise them in 2D. Achieved resolution is about a factor of two less than theoretical in both the cross-range and range dimensions.

The increasing concentration of carbon dioxide in the atmosphere is one of the causes of greenhouse effect. Therefore CO2 (carbon dioxide) ocean sequestration technologies such as dissolution into seawater are important in the mitigation of global warming. In this study solution processes of CO2 gas in seawater and synthetic seawater were experimentally studied under various pressures and temperatures to evaluate the solubilities of CO2 in seawater. The solubilities of CO2 in seawater and synthetic seawater were measured by a change in pressure due to absorption at pressures up to 3 MPa and the temperatures ranged from 276 K to 333 K. It was shown that the solubilities of CO2 were in the order of between 10-4 and 10-3 in seawater near atmospheric pressure. The values increase with an increase in pressure but decrease with an increase in temperature. The Henry's law constant of CO2 was about 105 MPa at a temperature of 277 K in seawater under atmospheric pressure and increased with an increase in temperature. The solubility of CO2 in synthetic seawater decrease with an increase in salt concentration. Empirical correlations for solubilities of CO2 in seawater at various temperatures and pressures were obtained based on the experimental data.

Designing and building structures that will withstand the unique challenges that exist in Subsea operations is no easy task. As deepwater wells are drilled to greater depths, engineers are confronted with a new set problems such as water depth, weather conditions, ocean currents, equipment reliability, and well accessibility, to name just a few. A definitive reference for engineers designing, analyzing and instilling offshore structures, Subsea Structural Engineering Handbook provides an expert guide to the key processes, technologies and equipment that comprise contemporary offshore structures. Written in a clear and easy to understand language, the book is based on the authors' 30 years of experience in the design, analysis and instillation of offshore structures. This book answers the above mentioned crucial questions as well as covers the entire spectrum of subjects in the discipline, from route selection and planning to design, construction, installation, materials and corrosion, inspection, welding, repair, risk assessment, and applicable design solutions. It yields a roadmap not only for the subsea engineer but also the project managers, estimators and regulatory personnel hoping to gain an appreciation of the overall issues and directed approaches to subsea engineering design solutions. The book gives Up-to-date technical overview of deepwater riser engineering; Coverage of design, analysis and, installation; Addresses issues concerning both fixed and floating platforms; Covers techincal equipment such as Subsea Control Systems, Pressure Piping, Connectors and Equipment Layout as well as Remotely-operated vehicles.

The development of Sulzer RTA low-speed marine diesel engines over the past three years is reviewed. A general overview is combined with details of various upgradings and new developments. The main advance has been the extension of the Sulzer RT-flex common-rail concept to more engine types. Reliability continues to be the most important subject for large marine engines. In this respect the latest piston-running behaviour of Sulzer engines is reported with very low consistent wear rates and savings in cylinder lubricating oil feed rates being achieved. The integrity of engine structures is also essential for reliability. Thus improvements in welded structures and their analysis by finite-element calculations are reviewed. Comments are also made on further improvements to the design of the main bearings including especially elasto-hydrodynamic calculations involving the structure crankshaft and shaft alignment. For good reliability of diesel engines built under licence Wartsila has set up so-called quality forums with its licensees to secure optimum exchange of knowledge to evaluate and improve quality processes where necessary and to make sure that weak points are immediately corrected. An overview of development work regarding cylinder lubrication for the future and the latest achievements in the reduction of exhaust emissions is presented. A new concept is described for optimising engines to make best use of waste heat recovery.

The Norway lobster Nephrops norvegicus is the target of the most valuable fishery in the Irish Sea. Scientific advice for management of the fisheries is provided to the European Commission by the International Council for the Exploration of the Sea (ICES). To date the ICES assessments of Irish Sea Nephrops stocks have been totally dependent on data from commercial fisheries. This study was established to obtain the first estimates of fecundity for Nephrops in the Irish Sea and improve the methods. Fecundity and losses of eggs during incubation were investigated from field and laboratory work conducted in 1997 and 1998. The estimates of fecundity were then used with values of larval production obtained in 1995 to give an estimate of spawning stock biomass of western Irish Sea female Nephrops. This paper summarizes these investigations presents estimates of biomass of mature female Nephrops in the western Irish Sea and compares these with the equivalent estimates from ICES assessments.

Ships of all shapes and sizes require some form of tender of daughter craft. Al ships require a tender for general embarkation and for MOB (man-overboard) recovery duties. VT Halmatic has been involved with both stern ramp and davit methods for launching and recovering daughter draft for many years. VT Halmatic has developed and implemented a number of structures and arrangements to improve launch and recovery methods for daughter craft. The requirements for daughter craft are discussed together with the various issues that need to be considered when developing a lifting arrangement for a particular craft. The structural design and analysis methodology is examined and important issues such as factors of safety in design and testing are considered. The role of finite element analysis to support this process is also described. The development of lifting arrangements and structures for larger boats with particular emphasis on the design of a single point lifting arrangements of a 13-tonne Pacific Rescue Craft built for service in the North Sea. This is followed by a review of the development of lifting arrangements for small RIBs - especially of single point lift structures that have been developed for three generations of Royal Navy seaboat RIBs. A number of case studies are presented as illustration.

The GAP (gravity actuated pipeline) concept is a mid-water pipe fluid transfer system linking a minimal production dry-tree unit such as a SeaStar TLP to a full production FPSO hub. The GAP is composed of a neutrally buoyant hard pipe section of flow lines suspended from the TLP and FPSO. Angled suspension members and weights connecting the pipe ends to the floaters apply tension to this pipe section which is globally reacted by the floater mooring systems. The feasibility of this concept has been shown for Brazilian and West African environment with tieback distances up to 30 km. The previous studies have confirmed the GAP system design fabrication and installation can be tailored to handle any number of flow functions between spread-moored floaters. It is explored how the GAP concept interacts with a TLP which is normally only vertically moored. The overall GAP TLP FPSO and mooring comprise a coupled dynamic system. It is proposed to investigate the coupled static and dynamic behaviour of the FPSO - GAP - TLP system in a typical West African environment. In particular the effect of the GAP on the dynamic and operational response of the TLP is investigated. The question of whether the tendon system of the TLP will need to be supplemented with an additional lateral mooring system to limit the static offset induced by the GAP is addressed.

Pikeperch and perch perform seasonal migrations between the Curonian Lagoon and the coastal waters of the Baltic Sea. The Curonian Lagoon is a freshwater basin while salinity in the coastal waters varies between 4.9-6.8 psu and the water temperature in the lagoon is generally higher than in the coastal waters. Field studies of growth and condition characteristics of pikeperch and perch were carried out with the aim to estimate growth differences under different salinity and temperature conditions. In addition an experimental study of the impact of salinity on the growth of young-of-the-year was performed to test the hypothesis that a brackish environment positively influences percids. Field observations revealed that body length condition factor fatness coefficient and fat content in muscles were significantly higher in individuals inhabiting the cooler brackish waters of the Baltic Sea. Study results suggest that under certain conditions brackish waters beneficially affect the growth of pikeperch and perch.

Extensive tidal flats and shallow waters used to exist in Mikawa Bay. About 17% of these have been lost due to land reclamation etc. It is known that deterioration in water purification ability due to the loss of many tidal flats and shallow waters has caused various environmental problems such as red tide oxygen-depleted water etc. In order to make navigation safer MLIT (the Ministry of Land Infrastructure and Transport) dredged the Nakayama Waterway at the mouth of Mikawa Bay between 1998 and 2004. In the areas of newly created tidal flats and shallow waters monitoring surveys were carried out on environmental conditions such as water quality sediment quality and benthos. Results of this monitoring are reported. Two years after the creation of the tidal flat bivalves such as Ruditapes philippinarum and Nactra chinensis increased. The recovery of benthos in particular is likely to be due to the reduction of oxygen-depleted water as a result of the creation of the shallow site. Improvement of water purification ability is expected due to the increase in bivalve shellfish which have high water purification ability.

The main field of application of a multi-beam echosounder is hydrographic surveying in other words acquisition of bathymetric data or bottom topography information - the topography of the seafloor. This kind of bathymetric data is needed by a large number of users for harbour and coastal zone management resource exploration hydrographic charting for safety of navigation and many other tasks. Tools for highly efficient investigation of the seafloor including rapid sediment classification as well as reliable object detection are of high interest to offshore construction projects. In the last few of years ATLAS Hydrographic has concentrated on the development of the next generation of hydrographic survey echosounders. One of the results is the ATLAS FANSWEEP 30 family of MBES (multi-beam echosounders). This family of sonars offers an innovative new approach of multi-beam echosounder technology for hydrographic surveys. The ATLAS FANSWEEP 30 COASTAL the first member of the ATLAS FANSWEEP 30 MBES family is breaking new ground. It represents a new generation of highly effective multi-beam echosounders for hydrographic data acquisition at highest accuracy and reliability demands. Its key features are: 8x SMP (simultaneous multi-ping) HOB (high-order beamforming) new ways of the ATLAS HPS for the data acquisition real-time processing evaluation and visualisation. Because of these characteristics the rate of effort of the FS30C together with its high standards in data quality

Coldwater reefs are comparable in size and structural complexity to the warm-water coral reefs of the tropics. Various cold-water coral ecosystems are described together with their known and potential global geographical distribution and their similarities to warm-water coral reefs. Observations from several locations around the world illustrate the state of these reefs and highlight their vulnerability to threats caused by human activities which have already destroyed or affected a large number of cold-water coral reefs. Key cold-water coral species are described followed by some consideration of their distribution and status regulations and measures. The aim is to raise awareness about cold-water coral reefs. Some recommendations are put forward for action to conserve protect and sustainably manage these fascinating but fragile ecosystems. Because of their extreme vulnerability there is a need for urgent and precautionary action to conserve and sustainable manage these cold water coral reefs. Such action includes the prohibition of destructive fishing practices including bottom trawling and the establishment of MPAs (marine protected areas). Conclusions are drawn and recommendations made. A scientist's statement is presented on protecting the world's deep-sea coral and sponge ecosystems. Recommended websites are listed.

Compared to connections between CHS (circular hollow sections) less attention has been devoted to multi-planar connections between RHS (rectangular hollow sections). Because of a lack of sufficient experimental and numerical evidence there is no sufficient information available for such connections. The strength of multi-planar overlap KK-joints in RHS and their counterparts uni-planar overlap K-joints are studied in more detail in order to determine the multi-planar effect. In this study the RHS sections are square. Based on this study the relationship between the strength of multi-planar overlap KK-joints and uni-planar overlap K-joints is determined. Further comparisons are made with existing design recommendations. An initial conclusion is that when using the formulae of the strength of uni-planar overlap K-joint to determine the strength of multi-planar overlap KK-joints no multi-planar correction has to be included if the strength is governed by the brace effective width criterion. However this investigation has also shown that for medium to higher chord slenderness chord face failure by yielding or buckling may occur and this failure mode is not covered in the current recommendations.

Designers of HSV (high-speed vessels) resort to light-weight design concepts since the hull weight plays a crucial role in the performance of such ships. Aluminium alloys appear certainly to be the best choice. However such material may be more prone to fatigue collapse and therefore aluminium alloy welded joints can be considered to be areas of weakness in a ship's structure. The fatigue behaviour of these joints is considered. The traditional methods for fatigue assessment of welded joints have some limitations and are extremely time consuming. In order to overcome these difficulties Risitano's method based on thermographic analysis is applied to predict the fatigue behaviour of welds. Experimental tests have been carried out to assess and compare the high-cycle endurance limits of different welded joints obtained by means of FSW (friction stir welding) and MIG techniques. The results obtained resorting to the TM (Thermographic Method) show good agreement with those derived from the experimental data represented through S-N curves. This is the first step in a research programme for the fatigue strength assessment of light alloy welded joints used in ship construction. Further research developments are outlined.

Long flexible circular cylinders known as marine risers linking the seabed to an offshore platform are exposed to strong sea currents which cause the flow around the risers to separate and initiate vortex shedding. Due to low structural damping the resultant lift and drag forces induce forced oscillations of the cylinder known as VIV (vortex-induced vibrations). High amplitude vibrations of the riser could potentially result in a high level of fatigue damage in a relatively short period of time. Design principles for deepwater risers are typically drawn from empirical knowledge and existing experimental data. These databases would further benefit from reliable computational studies on fluid-induced motions of structures. In an effort to gain a better understanding of the VIV phenomena 3D numerical simulations of VIV of circular cylinders are presented. Operating conditions that correspond to high Reynolds number flow low structural damping and allow for two-degree of freedom motion are considered. The numerical implementation makes use of overset (Chimera) grids in a multiple block environment where the workload associated with the blocks is distributed among multiple processors working in parallel. The 3D grids around the cylinder are allowed to undergo arbitrary motions with respect to fixed background grids eliminating the need for tedious grid regeneration at every time step.

All floating production systems must rely on some kind of marine risers for transport of the well stream from the seafloor to the platform and in many cases also for transport of processed oil and gas down to a pipeline. Among the many proposed riser concepts the SCR (steel catenary riser) is particularly promising due to its simplicity and low costs. This is in particular true if the heave motions of the floater are moderate as for TLPs (tension leg platforms) SPAR buoys and deep draught floaters. A key issue in design of catenary risers is to control stresses and fatigue damage in the touch down area. Vessel motions and waves will cause time varying stresses and because of restrictions from the seafloor contact bending stresses will often have peak values in this area. Another phenomenon that may contribute significantly to fatigue is VIV (vortex induced vibrations) in constant current. Although amplitudes are small compared to wave and motion induced stresses fatigue damage can be high because of the large number of stress cycles that may occur. Reliable prediction of bending stresses in the touchdown area from VIV is therefore desirable. Modelling aspects and analysis methods are discussed for calculating fatigue damage close to the touchdown point due to VIV. The method that is applied has previously been used for calculating VIV for free spanning pipelines - see Larsen et al. (2004) and Larsen and Koushan (2005).

For mooring chains of offshore floating production units API (American Petroleum Institute) recommends the use of its TxN fatigue curve considering the MBL (minimum breaking load) of an ORQ (oil rig quality) chain even if the chain has a higher grade. DNV (Det Norske Veritas) recommends the use of SxN fatigue curve where the stress is taken using the tension over the nominal area of the chain or wire rope. So it is easy to convert this SxN curve to a TxN curve or vice-versa. The geometry of the chain or wire rope and the material are implicit considered. To develop SxN curve for new accessories design it is necessary the using of FEM (finite elements method) to obtain the distribution of stresses and strains and the stress concentration factor and the SxN curves of the material. The analysis of the tension and the stress concentration factor will be used to obtain the slope and intercept parameters of the fatigue curve. The study developed for KS hook is presented together with how to obtain the fatigue curve for this accessory based on published papers rules and recent tests.