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A new hydrophone array and recording system has been developed for the collection of multi-channel broadband acoustic data at sea. Five of these systems have been constructed and successfully deployed at sea from a variety of research ships during several recent experiments. The typical array configuration is 16 elements at 3.75 spacing for a total aperture of 56.25 m but the arrays can be reconfigured with up to 64 hydrophones at any element spacing. The system can be deployed in a completely autonomous fashion or in conjunction with a surface buoy that provides remote system control and access to acoustic data files. The technical details of the arrays and recording systems as well as the different deployment configurations and techniques will be provided. In addition a general description of the use of these systems for geoacoustic inversion and acoustic data communications research is provided. Initially a general description of the design and construction of the arrays and data acquisition systems is presented and after this are sections that describe each component in greater detail. Finally the different deployment operations and their applications for underwater acoustic research are described.

A comprehensive analysis system for ship motion and wave load has been developed by Nippon Kaiji Kyokai in recent years. The system uses the latest 2D strip theory for conventional ships the high-speed strip theory for fast vehicles and the 3D sing-source Rankine source method for arbitrary ship types. At the first stage of this development a new analysis system for wave loads has been developed implementing the latest improvement on the strip theory. This 2D wave load analysis system called NewSTRIP is outlined together with its functions and capabilities. Its calculated results are compared with experimental measures as well as with other systems that use different methods.

Full-scope simulators have been used quite extensively for several decades in training ships' personnel. A new study is presented which has been carried out on five separate groups with an average of four students in each group without any sea service or simulator experience by using a new teaching method to improve the engineering skills of the students as well as their English language communication skills in a rather short period. The study includes a separate but parallel training for the same period practical hands-on assessment written and oral examinations on the operation of marine diesel engines. Assessment of the different training methods is carried out. Results are presented and conclusions drawn.

More and more ship owners are moving towards electric propulsion solutions. A new advancement in high-power electrical propulsion system is described which is based on large high-torque density induction machines specifically designed for marine propulsion fed by a new generation of medium voltage PPI (press-pack IGBT) converters. The system has been developed using the new PPIs which together with de-ionised water-cooling and appropriate modulation strategy give the ability to feed very high power induction machine. Very large applications can be considered such as cruise liners crude oil tankers container ships research vessels silent vessels and military vessels. The overall benefits are outlined in the conclusion.

Low-speed full ships such as the VLCC (Very Large Crude oil Carrier) have difficulty obtaining enough lifting force from a common rudder and therefore it is necessary to develop a high-lift rudder. The rudder of a ship is generally positioned behind the hull and propeller. Therefore rudder design should consider the interactions between hull propeller and rudder. In the present study the FLUENT code and body fitted mesh systems generated by the GRIDGEN program are adopted for the numerical simulations of flow characteristics around a rudder that is interacting with hull and propeller. SMM (sliding mesh model) is adopted to analyse the interaction between propeller rotation and wake flow behind the hull. Several numerical simulations are carried out to compare the interactions of hull-rudder propeller-rudder and hull-propeller-rudder. Also relationships between the interactions are considered. The results of the present numerical simulations show the variation of flow characteristics by the interaction between hull propeller and rudder

Marine engineers have sought effective and economical ways of protecting ship hulls and marine structures from the ravages of seawater and marine life for centuries. A brief history of the use of copper sheathing is given. Sea service evaluations of a number of ships are discussed particularly in terms of hull roughness. A state-of-the-art baseline method for sheathing is described and improvements are discussed. Three economic studies are highlighted; these compare conventional copper-bearing antifouling paint with an organo-tin copolymer antifoulant and copper-nickel sheathing. The sheathing of offshore structures is also considered including some successful cases where cost-savings have been demonstrated.

It is expected that construction work on a very large floating structure similar to the MEGA-FLOAT will increase. The working characteristic and the effect on board of oscillating ships by measuring the finger pulse is investigated. The effect of oscillating working conditions on the human body is investigated. Experiments are carried out to analyse the trend of decreasing work efficiency and the effect on workers' motion using various methods. The first experiment investigates the effect of oscillation upon physical motion. This experiment considers walking motion on the passage. The next experiment examined considers the effect on sensitive work. In this experiment the amount of the water poured into the empty bottle from the kettle is observed. The third experiment evaluates the relation between oscillation and thinking capability resulting from a simple test of calculation. Results of this study have shown that the decrease in work efficiency is closely connected to the delayed reaction of the human body with the oscillation.

This work is the first part of a test of turbulence models for the calculation of the flow field around ships. Turbulence modelling is an important part of computational fluid dynamics (CFD). The flow around ship-hulls is no exception, especially not around the stern. The flow around the stern is very complex: high Reynolds-number, three-dimensionally curved surfaces and a pair of strong longitudinal vortices emerging in the boundary-layer. No existing turbulence model is designed directly for this complex flow and just a few have been tested. This is, therefore, an area where development and testing of turbulence models are needed.

Now is an appropriate time to realise the objective of the PAAMES (Pan Asian Association of Maritime Engineering Societies) - to promote science and technology in maritime engineering through collaboration amongst the member organisations. It is well known that the Pan Asian region has become one of the world's largest and fastest growing economies where more than 85% of new ships are being built and 30% of the world's container volume is generated in the Northeast Asian region. Since competition is fierce in commercial sectors it is appropriate for personnel from academic and research institutes to initiate a joint research program within the framework of PAAMES. Among many other possible topics a new ship suitable for SSS (Short Sea Shipping) in the Northeast Asian region seems to be most appropriate from the viewpoint of the world-leading shipbuilding industry and mutual economic dependence of the region. This is also particularly relevant considering the global paradigm shift of logistics caused by high oil prices. Apart from attaining a consensus among the PAAMES members the most difficult problem will be to acquire funding.

Provision of support to warships is a specialist activity and the combination of complexity and market forces make derivation of a sustainable affordable support model particularly challenging. Faced with the challenge of sustaining an ageing fleet coupled with reducing budgets and a diminishing industrial base the UK MoD (Ministry of Defence) and Government acknowledge that the traditional Royal Navy Support model was no longer sustainable. Consequently the MoD commissioned the SSS (surface ship support) programme as a component of the over-arching UK Maritime Change Programme to examine the options to deliver sustainable effective and affordable support to complex warships. This paper will describe the UK MoD's future support model which aims to deliver high quality cost-effective support to ships of the Royal Navy with the expectation that it will deliver the environment for affordable support to the future fleet.

Bulk carrier loss statistics from 1980 to 1997 are presented. These statistics alerted IMO and IACS to the possible dangers of this ship type and initiated an in-depth research programme into bulk carriers. The culmination of this work has been mandatory legislation from IMO embodied in SOLAS and retrospective structural and stability requirements for existing bulk carriers and enhanced survivability and scantlings for newbuildings. The Unified Requirements (UR) developed by IACS are listed. Structural requirements for existing ships cover hold after bulkhead and double bottom. Areas at risk are identified and transverse bulkheads on existing single side skin bulk carriers are discussed. Typical upgrade requirements for handysize bulk carriers Panamax bulk carriers and Capesize bulk carriers are outlined. The advantages and disadvantages of homogeneous loading are summarised and the costs of steel reinforcement are outlined.

An overview of the impact of air pollution is reported together with reduction incentives (EROs - emission reduction objectives) for SOx NOx and CO2 in particular. There is a general consensus for a strong need to improve the air pollution situation. The current situation is assessed and it is considered how the current shipping industry is affected now and will be affected in the future. Possible developments are considered on a global EU-wide regional national and local level? The value of IMO's Marpol Annex 6 is examined as well as the efficacy of the Eurolateral approach as a whole. After this the aim of the EU acidification strategy is discussed. Then the effect of the present EU Sulphur Directive for Marine Diesel- and Gasoil is questioned together with its workability and the impact of the future EU Sulphur Directive on Heavy Fuel Oil. Next the present and future involvement for shipping is examined along with its relationship with Fuel Oil combustion cargo handling or operational needs on board ships. Finally

Sulzer RTA-series low-speed marine diesel engines are widely applied in the world fleet of deep-sea ships. The engines are continually updated to adapt them to suit market requirements and to incorporate in them the benefits of technical developments. The latest development in the Sulzer RTA series is the RT-flex60C which is only being built in the RT-flex version with common-rail fuel injection and full electronic control of engine functions. This new engine is designed primarily for the propulsion of fast feeder container vessels. There is a market requirement for such vessels to cover the rising demand for feeder services to and from the hub ports served by the large main-line container liners. The engine is described and its engine layout parameters and design particulars are given. Sea trials were successfully completed in September 2002 with the world's first low-speed marine diesel engine using common-rail fuel injection. The common-rail fuel injection in the Sulzer RT-flex system is described followed by other functions in the system. The engine is very powerful and compact and the numerous improvements introduced make the engine extremely reliable.

The limitations of the conventional stern tube design for the aftermost bearing supporting the tailshaft and propeller are discussed. The Mark I Turnbull split stern bearing is described. The design was intended to permit maintenance and survey withou removal of the propeller and line shafting. The seal and white metal bearing design are considered and fitting and alignment discussed. Pre-trial investigations by Lloyd's Register surveyors are described. Four ships of the Manchester Challenge class have been fitted with the Mark I bearing. The Mark II design is briefly mentioned. The Mark IV developed from new design criteria made necessary by the number of large vessels (50000 tons uwards) in service. Lubrication alignment and installation of the bearing are described. Survey and maintenance can be acrried out afloat.

The rules addressing safety at sea influence and characterise ship design at an early state especially in the case of vessels involved in passengers' transportation. For motor yachts in particular for those of significant dimensions and intended for commercial use the design constrains are prescribed in the MCA Code of Practice. Compliance with this code is appropriate for up to 12 passengers. However with ship size ever increasing in this area of the market designers are now considering complying directly with SOLAS requirements for passenger ships eliminating the 12-passenger limitation. So as far as the subdivision and damage stability requirements are concerned the new harmonised rules based on the probabilistic approach have been recently finalised at IMO and in subsequent years will be substituted by those based on the deterministic approach now existing within the current SOLAS. The significant revision of the regulation implies a strong change in the design procedure and in the definition of possible design solutions. Here the requirements contained in the three relevant rules (MCA SOLAS deterministic SOLAS probabilistic) are briefly described and compared

A brief review of various sources of energy dissipation in ship vibrations is made in which the importance of assessing damping at the design stage is stressed. A critical presentation of available analytical methods for introducing damping into dynamic calculations is given. It is concluded that damping characteristics cannot be systematically specified in the same way as other characteristics for example mass and stiffness distribution because of the complexity of the ship's structure. Experiments are therefore required. Modal damping values for various types of ships and loadings may be obtained by correlation with the results of systematic exciter tests thereby circumventing the need for estimating the complex excitation system in service conditions. A procedure for identifying damping parameters is described and applied to a 130000 cubic metre LNG vessel.

The continuing need to monitor and evaluate marine disposal sites that have been routinely used for the dumping of sewage sludge industrial wastes (both now phased out) and dredged material to sea (continued on licensed sites) from ships is noted: the range of sampling devices and survey methodology employed by CEFAS (Centre for Environment Fisheries and Aquaculture Science) to evaluate bottom topography and assess environmental impact is described together with observations and measurements typically made on sediments and benthic fauna (meiofauna and macro-epifauna). Two examples are included to illustrate the situation and findings at sites for dredged material disposal in Liverpool Bay (eastern Irish Sea) and sewage sludge disposal off the Tyne estuary (NE England): the beneficial use of dredged material is also briefly considered. A general discussion critically examines: models proposed for predicting changes in benthic communities in response to waste disposal; the design of sampling equipment and regimes; and the role of indicator organisms.

Forecasting is an essential aid to decision making. To date there have not been any tools capable of analysing the complex nature of the shipping industry. ANN (artificial neural networks) have become more common in use in business in recent times as they are effective in managing complex multiple input situations. Freight rates are very important within shipping because they effectively determine the ship owners' income from trading their ships. The derivation of freight rates is very complicated and calculating what affects freight rates is a daunting task since so many variable can be cited as influential. The oil tanker market is typical of the volatile shipping markets and here the possibility of accurately modelling its heartbeat freight rates is explored using a relatively innovative technique for predictive purposes within the domain of shipping. ANN are harnessed with the intention of modelling VLCC freight rates the VLCC orderbook and VLCC new building Prices. The results obtained are very promising and provide an ideal platform for further study.

Results are presented from a project called AMORES. This project focuses on improving lead-time and economic efficiency in ship and offshore platform repair and conversion in the Netherlands. Existing and newly developed photogrammetric measuring techniques were used to generate as-built models of double curved 3-D surfaces of ships and platforms. These were fed into standard CAD-CAM systems to engineer and manufacture new ship hull or platform parts to replace damaged areas. The main advantages of the new method are savings in lead-time (measurements engineering) and the replacing of costly manual labour by modern digital photogrammetry. The new developments are highlighted together with the difficulties experienced and the advantages of this new technique in ship repair.

The application of a resistant coating on ships offshore structures and pipelines is the primary prevention method of corrosion wastage in the marine industries. To guarantee coating integrity and to be able to thoroughly survey for corrosion wastage on marine structures new advanced nondestructive methods are being sought. A review of the developments in electromagnetic wave (advanced microwave and eddy current practices) sensors in elastic wave (advanced ultrasonic practices) sensors in time-resolved thermography (thermal imaging) in electrochemical sensors and in other emerging analytical techniques is presented. Each of the identified emerging technologies is assessed based on a set of requirements necessary to be an acceptable marine corrosion wastage testing tool. This technology review and assessment includes the use of both active and passive sensors and monitors as well as the use of sensor arrays. The state of development and availability of the most promising technologies are described.